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Dell 34XX, 38XX, 36XX, 32XX User Manual

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Dell PowerVault MD 32XX/34XX/36XX/38XX Series Storage Arrays
CLI Guide
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Notes, Cautions, and Warnings
NOTE: A NOTE indicates important information that helps you make better use of your computer.
CAUTION: A CAUTION indicates either potential damage to hardware or loss of data and tells you how to avoid the problem.
WARNING: A WARNING indicates a potential for property damage, personal injury, or death.
intellectual property laws. Dell™ and the Dell logo are trademarks of Dell Inc. in the United States and/or other jurisdictions. All other marks and names mentioned herein may be trademarks of their respective companies.
2015 - 02
Rev. A01
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Contents
1 CLI Command Updates......................................................................................16
New Commands..................................................................................................................................16
Updated Commands........................................................................................................................... 16
2 About The Command Line Interface...............................................................18
How To Use The Command Line Interface....................................................................................... 19
Usage Notes...................................................................................................................................19
CLI Commands..............................................................................................................................19
Command Line Parameters...........................................................................................................21
Formatting Considerations................................................................................................................. 25
Detailed Error Reporting..................................................................................................................... 25
Exit Status............................................................................................................................................ 26
Usage Examples...................................................................................................................................27
3 About The Script Commands........................................................................... 29
Script Command Structure.................................................................................................................30
Script Command Synopsis.................................................................................................................. 31
Recurring Syntax Elements................................................................................................................. 33
Usage Guidelines.................................................................................................................................38
Adding Comments To A Script File.................................................................................................... 38
4 Configuring A Storage Array............................................................................ 39
Configuring A Storage Array...............................................................................................................40
Determining What Is On Your Storage Array...............................................................................40
Saving A Configuration To A File.................................................................................................. 42
Using The Create Virtual Disk Command.................................................................................... 42
Using The Auto Configure Command......................................................................................... 45
Modifying Your Configuration............................................................................................................ 47
Setting The Storage Array Password.............................................................................................47
Setting Up SMTP And SNMP Alerts...............................................................................................48
Setting The RAID Controller Module Clocks............................................................................... 48
Setting The Storage Array Host Type........................................................................................... 48
Setting Modification Priority......................................................................................................... 49
Assigning Global Hot Spares.........................................................................................................50
Selecting The Event Levels For Alert Notifications...................................................................... 50
Configuring Alert Notifications..................................................................................................... 51
5 Using The Snapshot Feature.............................................................................52
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Before Using Snapshot CLI Commands.............................................................................................52
Snapshot Images And Groups............................................................................................................ 52
Snapshot Groups And Snapshot Consistency Groups...................................................................... 53
Snapshot Groups...........................................................................................................................53
Snapshot Consistency Groups......................................................................................................53
Understanding Snapshot Repositories...............................................................................................54
Snapshot Consistency Group Repositories..................................................................................54
Consistency Groups And Remote Replication.................................................................................. 54
Creating Snapshot Images..................................................................................................................55
Creating A Snapshot Image.......................................................................................................... 55
Deleting A Snapshot Image...........................................................................................................55
Creating A Consistency Group Snapshot Virtual Disk................................................................. 56
Creating A Consistency Group Snapshot Image..........................................................................57
Deleting A Snapshot Virtual Disk Or A Consistency Group Snapshot Virtual Disk..................... 57
Deleting A Consistency Group Snapshot Image..........................................................................57
Scheduling Snapshot Images........................................................................................................58
Starting, Stopping And Resuming A Snapshot Rollback.............................................................. 58
Creating A Snapshot Group..........................................................................................................59
Deleting A Snapshot Group..........................................................................................................60
Reviving A Snapshot Group.......................................................................................................... 60
Creating A Consistency Group.....................................................................................................60
Deleting A Consistency Group......................................................................................................61
Setting Consistency Group Attributes.......................................................................................... 61
Adding A Member Virtual Disk To A Consistency Group.............................................................62
Removing A Member Virtual Disk From A Consistency Group................................................... 62
Changing The Pre-read Consistency Check Setting Of An Overall Repository Virtual Disk..... 63
Setting Snapshot Virtual Disk Repository Virtual Disk Capacity.................................................. 64
Setting Snapshot Group Repository Virtual Disk Capacity.......................................................... 65
Reviving Disk Groups, Physical Disks, Snapshot Groups, And Snapshot Virtual Disks............... 65
6 Using The Snapshot (Legacy) Feature.............................................................67
Using Host Servers To Create An Initial Snapshot Virtual Disk......................................................... 68
Creating A Snapshot Virtual Disk........................................................................................................69
Enabling The Snapshot Virtual Disk Feature................................................................................ 69
Creating A Snapshot Virtual Disk With User-Assigned Physical Disks........................................ 69
Preparing Host Servers To Create An Initial Snapshot Virtual Disk............................................. 70
Creating The Initial Snapshot Virtual Disk.................................................................................... 70
Creating A Snapshot Virtual Disk With Software-Assigned Physical Disks..................................71
Creating A Snapshot Virtual Disk By Specifying A Number Of Physical Disks............................ 72
User-Defined Parameters..............................................................................................................73
Names Of Snapshot Virtual Disks And Repository Virtual Disks.................................................. 75
Changing Snapshot Virtual Disk Settings........................................................................................... 75
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Stopping And Deleting A Snapshot Virtual Disk.................................................................................76
Re-creating The Snapshot Virtual Disk ........................................................................................76
Preparing Host Servers To Re-create A Snapshot Virtual Disk.................................................... 77
Re-creating A Snapshot Virtual Disk............................................................................................. 77
7 Using The Virtual Disk Copy Feature...............................................................78
About Virtual Disk Copy......................................................................................................................78
Virtual Disk Copy Types...................................................................................................................... 78
Creating A Virtual Disk Copy.............................................................................................................. 80
Enabling The Virtual Disk Copy Feature.......................................................................................80
Determining Virtual Disk Copy Candidates..................................................................................80
Creating A Virtual Disk Copy........................................................................................................ 80
Preparing Host Servers To Create A Virtual Disk Copy................................................................81
Copying The Virtual Disk...............................................................................................................81
Viewing Virtual Disk Copy Properties.................................................................................................82
Changing Virtual Disk Copy Settings..................................................................................................83
Recopying A Virtual Disk.....................................................................................................................84
Preparing Host Servers To Recopy A Virtual Disk........................................................................84
Recopying The Virtual Disk...........................................................................................................85
Stopping A Virtual Disk Copy..............................................................................................................85
Removing Copy Pairs..........................................................................................................................86
Interaction With Other Features.........................................................................................................86
About Snapshot (Legacy) Premium Features With Virtual Disk Copy...............................................86
8 Using The Remote Replication Premium Feature........................................ 87
How Remote Replication Works........................................................................................................ 87
Replication Pairs And Replication Repositories................................................................................. 88
Differences Between Remote Replication And Remote Replication (Legacy) Features..................88
Link Interruptions Or Secondary Virtual Disk Errors..........................................................................88
Resynchronization.............................................................................................................................. 89
Remote Replication Group.................................................................................................................90
Previous Users Of Remote Replication (Legacy) Premium Feature..................................................90
Remote Replication Requirements And Restrictions........................................................................ 90
Primary And Secondary Virtual Disks..................................................................................................91
Setting Up Remote Replication...........................................................................................................91
Enabling The Remote Replication Premium Feature.........................................................................91
Activating The Remote Replication Premium Feature.......................................................................91
Creating A Remote Replication Group...............................................................................................91
Adding Primary Virtual Disk To Remote Replication Group..............................................................92
Changing Remote Replication Group Settings..................................................................................92
Adding Secondary Virtual Disk To Remote Replication Group.........................................................93
Suspending A Remote Replication Group......................................................................................... 93
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Deleting A Remote Replication Group...............................................................................................94
Removing A Virtual Disk Or Repository Virtual Disk From A Remote Replication Group................94
Disabling The Remote Replication Premium Feature........................................................................95
Deactivating The Remote Replication Premium Feature.................................................................. 95
Interaction With Other Premium Features.........................................................................................95
Standard Remote Replication Commands........................................................................................ 95
9 Using The Remote Replication (Legacy) Premium Feature........................97
How Remote Replication (Legacy) Works..........................................................................................97
Replication Repository Virtual Disks.............................................................................................98
Replication Relationships..............................................................................................................98
Data Replication............................................................................................................................99
Link Interruptions Or Secondary Virtual Disk Errors..................................................................100
Resynchronization...................................................................................................................... 100
Creating A Remote Replicated Pair.................................................................................................. 101
Performance Considerations...................................................................................................... 101
Enabling The Remote Replication (Legacy) Premium Feature..................................................102
Activating The Remote Replication (Legacy) Premium Feature................................................102
Determining Candidates For A Remote Replicated Pair............................................................104
Creating A Remote Replicated Pair............................................................................................ 104
Changing Remote Replication (Legacy) Settings.............................................................................105
Suspending And Resuming A Replication Relationship...................................................................106
Removing A Replication Relationship...............................................................................................107
Deleting A Primary Virtual Disk Or A Secondary Virtual Disk...........................................................107
Disabling The Remote Replication (Legacy) Premium Feature...................................................... 108
Deactivating The Remote Replication (Legacy) Premium Feature.................................................108
Interaction With Other Premium Features.......................................................................................108
Snapshot Virtual Disks.................................................................................................................108
Virtual Disk Copy.........................................................................................................................109
Storage Partitioning.................................................................................................................... 109
Virtual Disk Expansion................................................................................................................. 110
10 Maintaining A Storage Array......................................................................... 111
Routine Maintenance.........................................................................................................................111
Running A Media Scan................................................................................................................. 111
Running A Consistency Check With A Media Scan.................................................................... 112
Resetting A RAID Controller Module...........................................................................................113
Enabling RAID Controller Module Data Transfer........................................................................113
Resetting Battery Age.................................................................................................................. 113
Removing Persistent Reservations.............................................................................................. 113
Synchronizing RAID Controller Module Clocks......................................................................... 114
Locating Physical Disks................................................................................................................114
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Performance Tuning..........................................................................................................................114
Monitoring Performance.............................................................................................................114
Changing RAID Levels..................................................................................................................115
Changing Segment Size...............................................................................................................115
Defragmenting A Disk Group...................................................................................................... 116
Using SSD Cache............................................................................................................................... 116
Enabling SSD Cache For A Virtual Disk....................................................................................... 116
Creating SSD Cache.....................................................................................................................117
Adding Physical Disks To Existing SSD Cache............................................................................ 117
Removing Physical Disks From Existing SSD Cache...................................................................117
SSD Cache Performance Modeling.............................................................................................117
Additional Information About SSD Cache And Performance Modeling....................................118
Troubleshooting and Diagnostics.....................................................................................................118
Collecting Physical Disk Data......................................................................................................118
Diagnosing A RAID Controller Module....................................................................................... 118
Recovery Operations.........................................................................................................................119
Setting RAID Controller Module Operational Mode...................................................................119
Changing RAID Controller Module Ownership......................................................................... 120
Initializing A Physical Disk........................................................................................................... 120
Reconstructing A Physical Disk................................................................................................... 121
Initializing A Virtual Disk...............................................................................................................121
Redistributing Virtual Disks ......................................................................................................... 121
11 Script Commands........................................................................................... 122
Command Formatting Rules.............................................................................................................122
Firmware Compatibility Levels..........................................................................................................124
Commands Listed By Function.........................................................................................................124
Disk Group Commands...............................................................................................................124
Enclosure Commands.................................................................................................................125
Host Topology Commands.........................................................................................................125
iSCSI Commands.........................................................................................................................126
Physical Disk Commands............................................................................................................126
RAID Controller Module Commands..........................................................................................127
Remote Replication Commands................................................................................................ 128
Session Command...................................................................................................................... 129
Show String Command...............................................................................................................129
Snapshot Commands..................................................................................................................129
SSD Cache Commands...............................................................................................................129
Storage Array Commands...........................................................................................................130
Virtual Disk Commands...............................................................................................................132
Virtual Disk Copy Commands.....................................................................................................132
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12 Commands Listed Alphabetically................................................................ 133
Activate Remote Replication Feature............................................................................................... 133
Activate Storage Array Firmware...................................................................................................... 136
Add Member To Consistency Group................................................................................................136
Add Physical Disks To SSD Cache.................................................................................................... 138
Add Virtual Disk To Remote Replication Group...............................................................................139
Autoconfigure Storage Array.............................................................................................................141
Autoconfigure Storage Array Hot Spares......................................................................................... 143
Blink SSD Cache................................................................................................................................ 143
Cancel Remote Replication Group Role Reversal........................................................................... 144
Change SSD Cache Application Type.............................................................................................. 144
Check Remote Replication Status....................................................................................................145
Check Remote Replication Group Consistency.............................................................................. 145
Check Repository Consistency........................................................................................................ 146
Check Storage Array Connectivity....................................................................................................147
Check Virtual Disk Consistency........................................................................................................148
Clear Physical Disk Port Statistics.....................................................................................................149
Clear Remote Replication Fault........................................................................................................150
Clear Storage Array Configuration....................................................................................................151
Set Storage Array Core Dump...........................................................................................................152
Clear Storage Array Event Log..........................................................................................................152
Clear Storage Array Firmware Pending Area....................................................................................153
Clear Storage Array Recovery Mode.................................................................................................153
Clear Virtual Disk Reservations......................................................................................................... 153
Clear Virtual Disk Unreadable Sectors..............................................................................................154
Configure Automatic Support Bundle Collection............................................................................155
Convert Snapshot (Legacy) Virtual Disk To Snapshot Group.......................................................... 155
Create Consistency Group............................................................................................................... 156
Create Consistency Group Snapshot Image....................................................................................158
Create Consistency Group Snapshot Virtual Disk........................................................................... 159
Create Consistency Group Snapshot Virtual Disk Mapping............................................................ 161
Create Disk Group.............................................................................................................................162
Create Disk Pool................................................................................................................................165
Create Host....................................................................................................................................... 169
Create Host Group............................................................................................................................169
Create Host Port................................................................................................................................170
Create iSCSI Initiator..........................................................................................................................171
Create RAID Virtual Disk (Automatic Physical Disk Select)...............................................................171
Create RAID Virtual Disk (Free Extent Base Select).......................................................................... 174
Create RAID Virtual Disk (Manual Physical Disk Select)................................................................... 176
Create RAID Virtual Disk On A Disk Pool..........................................................................................179
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Create Read-Only Snapshot Virtual Disk..........................................................................................181
Create Remote Replication...............................................................................................................182
Create Remote Replication Group...................................................................................................184
Create Snapshot Group.................................................................................................................... 187
Create Snapshot Image.................................................................................................................... 189
Create Snapshot (Legacy) Virtual Disk............................................................................................. 190
Create Snapshot Virtual Disk............................................................................................................ 196
Create SSD Cache.............................................................................................................................198
Create Storage Array Security Key....................................................................................................199
Create Virtual Disk Copy...................................................................................................................201
Deactivate Remote Replication (Legacy).........................................................................................203
Delete Consistency Group............................................................................................................... 203
Delete Consistency Group Snapshot Image................................................................................... 204
Delete Consistency Group Snapshot Virtual Disk........................................................................... 205
Delete Disk Group............................................................................................................................ 205
Delete Disk Pool............................................................................................................................... 206
Delete Host....................................................................................................................................... 206
Delete Host Group............................................................................................................................207
Delete Host Port............................................................................................................................... 207
Delete iSCSI Initiator.........................................................................................................................208
Delete Snapshot Group....................................................................................................................209
Delete Snapshot Image.................................................................................................................... 209
Delete Snapshot (Legacy) Virtual Disk.............................................................................................. 211
Delete Snapshot Virtual Disk.............................................................................................................212
Delete Snapshot Virtual Disk or Delete Snapshot Virtual Disk Schedule........................................ 212
Delete SSD Cache............................................................................................................................. 213
Delete Virtual Disk............................................................................................................................. 213
Delete Virtual Disk On A Disk Pool................................................................................................... 214
Diagnose RAID Controller Module................................................................................................... 215
Diagnose RAID Controller Module iSCSI Host Cable.......................................................................217
Diagnose Remote Replication..........................................................................................................218
Disable Storage Array Feature...........................................................................................................219
Display Automatic Support Bundle Collection Configuration........................................................220
Display Support Bundle Collection Schedule.................................................................................. 221
Download Enclosure Management Module Firmware....................................................................221
Download Physical Disk Firmware...................................................................................................222
Download Storage Array Firmware/NVSRAM.................................................................................. 223
Download Storage Array Physical Disk Firmware............................................................................223
Download Storage Array NVSRAM...................................................................................................224
Enable Disk Group Security.............................................................................................................. 225
Enable Disk Pool Security.................................................................................................................226
Enable or Disable ODX..................................................................................................................... 226
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Enable Or Disable SSD Cache For A Virtual Disk............................................................................. 227
Enable or Disable VAAI..................................................................................................................... 228
Enable RAID Controller Module Data Transfer................................................................................228
Enable Storage Array Feature........................................................................................................... 229
Establish Remote Replicated Pair.....................................................................................................229
Increase Virtual Disk Capacity On A Disk Pool................................................................................230
Load Storage Array DBM Database...................................................................................................231
Modify Disk Pool............................................................................................................................... 233
Recopy Virtual Disk Copy................................................................................................................. 233
Recover RAID Virtual Disk.................................................................................................................235
Re-Create Remote Replication Repository Virtual Disk..................................................................239
Re-Create Snapshot......................................................................................................................... 242
Reduce Disk Pool Capacity.............................................................................................................. 244
Register SNMP Community..............................................................................................................245
Register SNMP Trap Destination...................................................................................................... 245
Reinitialize Thin Virtual Disk............................................................................................................. 246
Remove Incomplete Remote Replicated Pair From Remote Replication Group...........................247
Remove Member Virtual Disk From Consistency Group................................................................248
Remove Physical Disks From SSD Cache........................................................................................ 248
Remove Remote Replication........................................................................................................... 249
Remove Virtual Disk Copy................................................................................................................250
Remove Virtual Disk From Remote Replication Group...................................................................250
Remove Virtual Disk LUN Mapping...................................................................................................251
Rename A Snapshot Virtual Disk...................................................................................................... 252
Rename SSD Cache.......................................................................................................................... 253
Repair Virtual Disk Consistency........................................................................................................253
Replace Physical Disk....................................................................................................................... 254
Reset iSCSI IP Address...................................................................................................................... 255
Reset Physical Disk........................................................................................................................... 256
Reset RAID Controller Module......................................................................................................... 257
Reset Remote Replication Group Statistics..................................................................................... 258
Reset Storage Array Battery Install Date.......................................................................................... 259
Reset Storage Array iSCSI Baseline.................................................................................................. 260
Reset Storage Array SAS PHY Baseline............................................................................................ 260
Reset Storage Array Virtual Disk Distribution................................................................................... 261
Resume Consistency Group Snapshot Virtual Disk......................................................................... 261
Resume Remote Replication............................................................................................................262
Resume Remote Replication Group................................................................................................ 263
Resume Snapshot Image Rollback.................................................................................................. 264
Resume Snapshot (Legacy) Rollback............................................................................................... 265
Resume Snapshot Virtual Disk..........................................................................................................265
Resume SSD Cache.......................................................................................................................... 267
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Revive Disk Group.............................................................................................................................267
Revive Disk Pool................................................................................................................................268
Revive Physical Disk..........................................................................................................................268
Revive Snapshot Group.................................................................................................................... 269
Revive Snapshot Virtual Disk............................................................................................................ 269
Save Enclosure Log Data..................................................................................................................270
Save Input Output RAID Controller Module (IOC) Dump............................................................... 270
Save Physical Disk Log...................................................................................................................... 271
Save RAID Controller Module NVSRAM............................................................................................271
Save Remote Replication Group Statistics.......................................................................................272
Save Storage Array Configuration.................................................................................................... 274
Save Storage Array Core Dump........................................................................................................275
Save Storage Array DBM Database...................................................................................................275
Save Storage Array DBM Validator Information File.........................................................................277
Save Storage Array Events................................................................................................................ 278
Save Storage Array iSCSI Statistics................................................................................................... 279
Save Storage Array Performance Statistics......................................................................................280
Save Storage Array SAS PHY Counts................................................................................................280
Save Storage Array State Capture.....................................................................................................281
Save Storage Array Support Data......................................................................................................281
Schedule Support Bundle Collection Configuration.......................................................................282
Scheduling Snapshots...................................................................................................................... 283
Set Consistency Group Attributes....................................................................................................285
Set Consistency Group Snapshot Virtual Disk.................................................................................286
Set Disk Group ................................................................................................................................. 286
Set Disk Group Forced State............................................................................................................ 288
Set Disk Pool.....................................................................................................................................288
Set Disk Pool Complete....................................................................................................................289
Set Enclosure Attribute.....................................................................................................................290
Set Enclosure Identification............................................................................................................. 290
Set Event Alert Filtering.....................................................................................................................291
Set Foreign Physical Disk to Native..................................................................................................292
Set Host.............................................................................................................................................293
Set Host Channel..............................................................................................................................294
Set Host Group................................................................................................................................. 295
Set Host Port..................................................................................................................................... 295
Set iSCSI Initiator...............................................................................................................................296
Set iSCSI Target Properties...............................................................................................................297
Set Physical Disk Channel Status......................................................................................................297
Set Physical Disk Hot Spare..............................................................................................................298
Set Physical Disk State......................................................................................................................299
Set RAID Controller Module.............................................................................................................299
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Set Read-Only Snapshot Virtual Disk To A Read/Write Virtual Disk............................................... 303
Set Remote Replication....................................................................................................................303
Set Remote Replication Group........................................................................................................ 306
Set Session........................................................................................................................................ 309
Set Snapshot Group Attributes......................................................................................................... 310
Set Snapshot Group Media Scan.......................................................................................................311
Set Snapshot Group Repository Virtual Disk Capacity.....................................................................312
Set Snapshot Group Schedule..........................................................................................................313
Set Snapshot (Legacy) Virtual Disk................................................................................................... 314
Set Snapshot Virtual Disk Media Scan...............................................................................................317
Set Snapshot Virtual Disk Repository Virtual Disk Capacity.............................................................318
Set Storage Array...............................................................................................................................319
Set Storage Array Enclosure Positions............................................................................................. 322
Set Storage Array ICMP Response....................................................................................................323
Set Storage Array iSNS Server IPv4 Address.....................................................................................323
Set Storage Array iSNS Server IPv6 Address.....................................................................................324
Set Storage Array iSNS Server Listening Port...................................................................................324
Set Storage Array Learn Cycle.......................................................................................................... 325
Set Storage Array Redundancy Mode.............................................................................................. 325
Set Storage Array Security Key......................................................................................................... 326
Set Storage Array Time..................................................................................................................... 326
Set Storage Array Unnamed Discovery Session...............................................................................327
Set Thin Virtual Disk Attributes......................................................................................................... 327
Set Virtual Disk.................................................................................................................................. 329
Set Virtual Disk Attributes For A Disk Pool....................................................................................... 332
Set Virtual Disk Copy.........................................................................................................................337
Set Virtual Disk Mapping...................................................................................................................338
Show Blocked Events....................................................................................................................... 340
Show Consistency Group Snapshot Image.....................................................................................340
Show Current iSCSI Sessions............................................................................................................341
Show Disk Group.............................................................................................................................. 342
Show Disk Group Export Dependencies..........................................................................................343
Show Disk Group Import Dependencies......................................................................................... 343
Show Disk Pool.................................................................................................................................344
Show Host Ports............................................................................................................................... 344
Show Physical Disk........................................................................................................................... 345
Show Physical Disk Channel Statistics............................................................................................. 347
Show Physical Disk Download Progress..........................................................................................347
Show RAID Controller Module.........................................................................................................348
Show RAID Controller Module NVSRAM......................................................................................... 349
Show Remote Replication Group.................................................................................................... 349
Show Remote Replication Group Synchronization Progress.........................................................350
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Show Remote Replication Virtual Disk Candidates......................................................................... 351
Show Remote Replication Virtual Disk Synchronization Progress................................................. 352
Show SNMP Communities............................................................................................................... 352
Show SNMP MIB II System Group Variables....................................................................................354
Show Snapshot Group......................................................................................................................354
Show Snapshot Image......................................................................................................................356
Show Snapshot Virtual Disks............................................................................................................ 357
Show SSD Cache.............................................................................................................................. 358
Show SSD Cache Statistics...............................................................................................................359
Show Storage Array.......................................................................................................................... 363
Show Storage Array Auto Configure................................................................................................365
Show Storage Array Core Dump......................................................................................................366
Show Storage Array DBM Database................................................................................................. 367
Show Storage Array Host Topology.................................................................................................367
Show Storage Array LUN Mappings.................................................................................................368
Show Storage Array Negotiation Defaults....................................................................................... 369
Show Storage Array ODX Setting.....................................................................................................369
Show Storage Array Power Information.......................................................................................... 370
Show Storage Array Unconfigured iSCSI Initiators..........................................................................370
Show Storage Array Unreadable Sectors..........................................................................................371
Show String........................................................................................................................................371
Show Thin Virtual Disk...................................................................................................................... 372
Show Virtual Disk...............................................................................................................................373
Show Virtual Disk Action Progress................................................................................................... 374
Show Virtual Disk Copy.....................................................................................................................375
Show Virtual Disk Copy Source Candidates.................................................................................... 376
Show Virtual Disk Copy Target Candidates..................................................................................... 376
Show Virtual Disk Performance Statistics.........................................................................................377
Show Virtual Disk Reservations.........................................................................................................377
Start Configuration Database Diagnostic.........................................................................................378
Start Consistency Group Snapshot Rollback...................................................................................378
Start Disk Group Blink.......................................................................................................................380
Start Disk Group Defragment...........................................................................................................380
Start Disk Group Export....................................................................................................................380
Start Disk Group Import....................................................................................................................381
Start Disk Pool Locate.......................................................................................................................382
Start Enclosure Blink.........................................................................................................................382
Start Input Output RAID Controller Module (IOC) Dump............................................................... 383
Start iSCSI DHCP Refresh................................................................................................................. 383
Start Physical Disk Blink....................................................................................................................384
Start Physical Disk Channel Blink.....................................................................................................384
Start Physical Disk Initialize.............................................................................................................. 385
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Start Physical Disk Reconstruction...................................................................................................385
Start Remote Replication Synchronization......................................................................................386
Start Remote Replication (Legacy) Synchronization.......................................................................386
Start Secure Physical Disk Erase.......................................................................................................387
Start Snapshot Rollback....................................................................................................................387
Start Snapshot Image Rollback........................................................................................................ 388
Start SSD Cache Performance Modeling.........................................................................................389
Start Storage Array Blink...................................................................................................................390
Start Storage Array Configuration Database Diagnostic.................................................................390
Start Storage Array iSCSI Refresh..................................................................................................... 392
Start Virtual Disk Initialization...........................................................................................................392
Stop Configuration Database Diagnostic........................................................................................ 393
Stop Consistency Group Snapshot Rollback...................................................................................393
Stop Consistency Group Snapshot Virtual Disk.............................................................................. 394
Stop Disk Group Blink.......................................................................................................................395
Stop Disk Pool Locate.......................................................................................................................395
Stop Enclosure Blink.........................................................................................................................395
Stop Pending Snapshot Images On Consistency Group................................................................ 396
Stop Physical Disk Blink....................................................................................................................396
Stop Physical Disk Channel Blink.....................................................................................................396
Stop Physical Disk Replace...............................................................................................................397
Stop Snapshot Group Image............................................................................................................398
Stop Snapshot Group Pending Snapshot Images........................................................................... 398
Stop Snapshot (Legacy)....................................................................................................................399
Stop Snapshot (Legacy) Rollback.................................................................................................... 400
Stop Snapshot Rollback....................................................................................................................401
Stop Snapshot Image Rollback.........................................................................................................401
Stop Snapshot Virtual Disk............................................................................................................... 402
Stop SSD Cache Performance Modeling.........................................................................................403
Stop Storage Array Blink...................................................................................................................405
Stop Storage Array Configuration Database Diagnostic.................................................................405
Stop Storage Array iSCSI Session.....................................................................................................406
Stop Storage Array Physical Disk Firmware Download...................................................................406
Stop Virtual Disk Copy......................................................................................................................406
Suspend Remote Replication...........................................................................................................407
Suspend Remote Replication Group............................................................................................... 408
Suspend SSD Cache......................................................................................................................... 408
Test Remote Replication Group Connectivity................................................................................ 409
Test SNMP Trap Destination.............................................................................................................410
Unregister SNMP Community...........................................................................................................411
Unregister SNMP Trap Destination................................................................................................... 411
Update SNMP Community................................................................................................................411
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Update SNMP MIB II System Group Variables..................................................................................412
Update SNMP Trap Destination........................................................................................................413
Validate Storage Array Security Key..................................................................................................413
13 Sample Script Files..........................................................................................415
Configuration Script Example 1........................................................................................................ 415
Configuration Script Example 2........................................................................................................417
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1

CLI Command Updates

This chapter reflects new and updated commands that are available for use with the Dell PowerVault MD 32XX/34XX/36XX/38XX Series storage arrays.
NOTE: Not all commands are valid with all storage arrays. Some commands are specific to certain platforms.
CAUTION: Script commands are capable of changing the configuration and may cause loss of data if not used correctly. Command operations are performed as soon as you run the commands. Before using the script commands, ensure that you have backed up all data, and have saved the current configuration so that you can reinstall it if the changes do not work.

New Commands

The following commands have been added to this guide to reflect the additional functionality available in the PowerVault MD32XX, MD34XX, MD36XX, and MD38XX.
• Recover SAS Port Mis-Wire
• Reduce Disk Pool Capacity
• Register SNMP Community
• Register SNMP Trap Destination
• Set Event Alert Filtering
• Show Blocked Events
• Show SNMP Communities
• Show SNMP MIB II System Group Variables
• Show Storage Array Power Information
• Test SNMP Trap Destination
• Unregister SNMP Community
• Unregister SNMP Trap Destination
• Update SNMP Community
• Update SNMP Trap Destination
• Update SNMP MIB II System Group Variables

Updated Commands

The syntax of the following commands has been modified, updated, or enhanced since the last release of this document.
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NOTE: not all commands are valid with all storage arrays. Some commands are specific to certain platforms.
• Activate Remote Replication (Legacy)
• Download Storage Array NVSRAM
• Resume Remote Replication Group
• Resume Snapshot (Legacy) Rollback
• Set RAID Controller Module
• Set Remote Replication (Legacy)
• Set Storage Array
• Start Remote Replication Synchronization
• Stop Snapshot (Legacy) Rollback
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2

About The Command Line Interface

This guide is intended for system administrators, developers, and engineers who need to use the command line interface (CLI) tool and its associated commands and script files. Selected CLI commands perform functions that can also be accessed from the Modular Disk (MD) Storage Manager, which is the graphical user interface (GUI) to the storage array. See the Administrator's Guide, which describes the Storage Manager software that is used to create and manage multiple storage arrays. For additional information, see the hardware and software manuals that shipped with your system.
NOTE: Always check for updates on dell.com/support and read the updates first because they often supersede information in other documents.
NOTE: CLI commands do not have interactive warnings for destructive commands.
CLI is a software tool that enables storage array installers, developers, and engineers to configure and monitor storage arrays. Using the command line interface, you can issue commands from an operating system prompt, such as the Microsoft Windows command prompt (C:\) or a Linux operating system terminal.
Each command performs a specific action for managing a storage array or returning information about the status of a storage array. You can enter individual commands, or run script files when you need to perform operations more than once (such as installing the same configuration on several storage arrays). A script file can be loaded and run from the command line interface. You can also run commands in an interactive mode. Interactive mode enables you to connect to a specific storage array and rapidly enter a command, determine the effect on the storage array, and then enter a new command.
The command line interface gives you direct access to a script engine utility in the Dell PowerVault Modular Disk Storage Manager software (MD Storage Manager). The script engine reads the commands, or runs a script file, from the command line and performs the operations instructed by the commands.
You can use the command line interface to perform the following functions:
• Directly access the script engine and run commands in interactive mode or using a script file.
• Create script command batch files to be run on multiple storage arrays when you need to install the
same configuration on different storage arrays.
• Run script commands on a storage array directly connected to a host, a storage array connected to a
host by an Ethernet, or a combination of both.
• Display configuration information about the storage arrays.
• Add storage arrays to and remove storage arrays from the management domain.
• Perform automatic discovery of all storage arrays attached to the local subnet.
• Add or delete Simple Network Management Protocol (SNMP) trap destinations and e-mail alert
notifications.
• Specify the mail server and sender e-mail address or Simple Mail Transport Protocol (SMTP) server for
alert notifications.
• Direct the output to a standard command line display or to a named file.
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How To Use The Command Line Interface

Using the CLI commands, you can access the script engine, specify which storage array receives the script commands, and set operation environment parameters.
A CLI command consists of the following elements:
• The term SMcli
• Storage array identifier
• Parameters
• Script commands
The following syntax is the general form of a CLI command:
SMcli storageArray parameters script-commands;
where,
SMcli invokes the command line interface.
storageArray is the host name or IP address of the storage array.
parameters are the CLI parameters that define the environment and purpose of the command.
script-commands are the commands or name of the script file containing the script commands.
The script commands are the storage array configuration commands. About The Script Commands presents an overview of the script commands. Script commands provide definitions, syntax, and parameters for the script commands.

Usage Notes

If you enter SMcli and a storage array name but do not specify CLI parameters, script commands, or a script file, the command line interface runs in interactive mode. Interactive mode enables you to run individual commands without prefixing the commands with SMcli. You can enter a single command, view the results, and enter the next command without typing the complete SMcli string. Interactive mode is useful for determining configuration errors and quickly testing configuration changes.
If you enter SMcli without any parameters or with an incorrect parameter, the script engine returns usage information.
NOTE: The SMcli command is installed under the client directory of the selected path during a management station install of the MD Storage Manager software.
NOTE: The SMcli command should be a component of the system environment command path.

CLI Commands

This section lists the CLI commands you can use to perform the following functions:
• Identify storage arrays
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• Set passwords
• Add storage arrays
• Specify communication parameters
• Enter individual script configuration commands
• Specify a file containing script configuration commands
The following are general forms of the CLI commands, showing the parameters and terminals used in each command. The table below lists definitions for the parameters shown in the CLI commands.
Table 1. Command Name Conventions
Parameter Definition
a|b
pipe symbol indicating alternative ("a" or "b")
italicized-words terminals
[...] (square brackets) zero or one occurrence
{...} (curly brackets) zero or more occurrences
<...> (angle brackets) occurrence exceeds maximum limit of 30
characters
(a|b|c)
choose only one of the alternatives
bold terminals
SMcli host-name-or-IP-address [host-name-or-IPaddress]
command; {command2};"]
[-c " [-n storage-array-name | -w WWID] [-o outputfile][-p password][-e][-S]
SMcli host-name-or-IP-address [host-name-or-IP-address] [-f scriptfile] [-n storage-array-name | -w WWID]
outputfile] [-p password] [-e] [-S]
[-o
SMcli (-n storage-array-name | -w WWID) [-c "command; {command2};"] [-o outputfile][-p password][-e][-S]
SMcli (-n storage-array-name | -w WWID) [-f scriptfile] [-o outputfile] [-p password] [-e] [-S]
SMcli (-n storage-array-name | -w WWID)
outputfile][-p password][-e][-S]
[-o
SMcli -a email:email-address [host-name-or-IP-address1 [host-name-or-IP-address2]] [-n storage-array-name | -w WWID | -h host-name |
-r (host_sa | direct_sa)] [-I information-to-include][-q frequency][-S]
SMcli -x email:email-address [host-name-or-IP-address1 [host-name-or-IP-address2]] [-n storage-array-name | -w WWID | -h host-name |
-r (host_sa | direct_sa)] [-S]
SMcli (-a | -x) trap:community, host-name-or-IP-address [host-name-or-IP-address1
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[host-name-or-IP-address2]] [-n storage-array-name | -w WWID | -h host-name |
-r (host_sa | direct_sa)] [-S]
SMcli -d [-w][-i][-s][-v][-S]
SMcli -m host-name-or-IP-address -F email-address [-g contactInfoFile][-S]
SMcli -A [host-name-or-IP-address [host-name-or-IP-address]] [-S]
SMcli -X (-n storage-array-name | -w WWID |
-h host-name)
SMcli -?

Command Line Parameters

Table 2. Command Line Parameters
Parameter Definition
host‑name-or-IP-address
-A
-a
Specify either the host name or the Internet Protocol (IP) address of an in-band managed storage array (IPv4 or IPv6) or an out-of-band managed storage array (IPv4 or IPv6).
• If you manage a storage array by using a host connected directly to the storage array (in‑band storage management), you must use the -n parameter if more than one storage array is connected to the host.
• If you manage a storage array through an Ethernet connection (out-of-band storage management), you must specify the host‑name‑or‑IP‑address of the redundant array of independent disks (RAID) controller modules.
• If you have previously configured a storage array in the graphical user interface (GUI) of the MD Storage Manager, you can specify the storage array by its user‑supplied name by using the -n parameter.
Use to add a storage array to the configuration files. If you do not follow the -A parameter with a host‑name‑or‑IP‑address, automatic discovery scans the local subnet for storage arrays.
Use to add an SNMP trap destination or an e-mail address alert destination.
• When adding an SNMP trap destination, the SNMP community is automatically defined as the community name for the trap and the host is the IP address or Domain Name Server (DNS) host name of the system to which the trap should be sent.
• When adding an e-mail address for an alert destination, the email-address is the e-mail address to which to send the alert message.
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Parameter Definition
-c
-d
-e
-F (uppercase)
-f (lowercase)
Use to indicate that you are entering one or more script commands to run on the specified storage array. Terminate each command by using a semicolon (;).
You cannot place more than one -c parameter on the same command line. You can include more than one script command after the -c parameter.
Use to display the contents of the script configuration file.
Use to disable syntax checking when executing the current CLI command.
Use to specify the e-mail address from which all alerts will be sent.
Use to specify a file name containing script commands intended to run on the specified storage array.
This parameter is similar to the -c parameter in that both are intended for running script commands. The -c parameter allows you to execute individual script commands. The -f
(lowercase)
script commands contained in a file.
parameter allows you to execute
-g
NOTE: By default, any errors encountered when running the script commands in a file are ignored, and the file continues to run. To override this behavior, use the set session errorAction=stop command in the script file.
Use to specify an ASCII file that contains e-mail sender contact information to include in all e-mail alert notifications. The CLI assumes the ASCII file is text only, without delimiters or any expected format. A typical file contains the following information:
• Name
• Title
• Company
• Phone
• Pager
NOTE: You can use any file name that your operating system supports. You must not use userdata.txt. Some operating systems reserve userdata.txt for system information.
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Parameter Definition
-h
-I
-i
-m
-n
Use with the -a and -x parameters to specify the host name that is running the SNMP agent to which the storage array is connected.
Use to specify the type of information to be included in the e-mail alert notifications. The following are valid information arguments:
• eventOnly— Only event information is included in the e-mail.
• profile— Event and array profile information is included in the e-mail.
• supportBundle— Event and support bundle information is included in the e-mail.
NOTE: You can enter only one information argument each time you execute the command. If you want all of the information, you must run the command three times.
Use with the -d parameter to display the IP address of the known storage arrays.
Use to specify the host name or IP address of the e-mail server from which to send e-mail alert notifications.
Use to specify the name of the storage array on which to run the script commands. This name is optional when you use host‑name-or-IP- address; however, if you are using the in-band method for managing the storage array, you must use the array is connected to the host at the specified address. The storage array name is required when host‑name-or-IP-address is not used; however, the name of the storage array configured for use in the MD Storage Manager GUI (that is, listed in the configuration file) must not be a duplicate name of any other configured storage array.
-n parameter if more than one storage
-o
-p
Use with the -c or -f parameter to specify a file name for all output text that is a result of running the script commands.
Use to specify the password for the storage array on which to run commands. A password is not necessary under the following conditions:
• A password has not been set on the storage array.
• The password is specified in a script file that is running.
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Parameter Definition
• The storage array password is specified by using the -c parameter and the set session
password=password command.
-q
-r
Use to specify how frequently to include additional profile or support bundle information in the e-mail alert notifications. An e-mail alert notification that contains at least the basic event information is always generated for every critical event. If you set the-I parameter to eventOnly, the only valid argument for -q is everyEvent. If you set the-I parameter to either profile or supportBundle, this information is included with the e-mails with the frequency specified by the-q parameter.
Valid frequency arguments are:
• everyEvent— Information is returned with every e-mail alert notification.
• 2— Information is returned no more than once every two hours.
• 4— Information is returned no more than once every four hours.
• 8— Information is returned no more than once every eight hours.
• 12— Information is returned no more than once every 12 hours.
• 24— Information is returned no more than once every 24 hours.
Use with the -a or -x parameter to specify the name of a management station. The name of a management station can be either direct_sa (out­of-band storage array) or host_sa (in-band storage arrays [host-agent]). The -r parameter enables you to set or change the alert notifications for all storage arrays under each management station.
-S (uppercase)
-s (lowercase)
24
Use to suppress the informational messages describing command progress that appear when running script commands. (Suppressing informational messages is also called silent mode.) This parameter suppresses the following messages:
• Performance syntax check
• Syntax check complete
• Executing script
• Script execution complete
• SMcli completed successfully
Use with the -d parameter to display the alert settings in the configuration file.
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Parameter Definition
-v
-X (uppercase)
-x (lowercase)
-?
Use with the -d parameter to display the current global status of the known devices in the storage array configuration file. (The configuration file lists all of the devices in a storage array configuration and the relationship between the devices. Use the configuration file to reconstruct a storage array).
Use to delete a storage array from the configuration file. (The configuration file lists all of the devices in a storage array configuration and the relationship between the devices. Use the configuration file to reconstruct a storage array).
Use to remove an SNMP trap destination or an e­mail address alert destination. The community is the SNMP community name for the trap, and the host is the IP address or DNS host name of the system to which you want the trap sent.
Use this parameter to display usage information about the CLI commands.

Formatting Considerations

Quotation marks (" ") used as part of a name or label require special consideration when you run the CLI and script commands on a Microsoft Windows operating system. The following explains the use of quotation marks in names while running CLI and script commands on Windows.
When quotation marks (" ") are part of an argument, you must insert a backslash (\) before each quotation mark character unless you are in interactive mode. For example:
-c "set storageArray userLabel=\"Engineering\";"
where, Engineering is the storage array name.
You cannot use quotation marks (" ") as part of a character string (also called string literal) within a script command. For example, you cannot enter the following string to set the storage array name to "Finance"Array:
-c "set storageArray userLabel= \"\"Finance\"Array\";"
On a Linux operating system, the delimiters around names or labels are single quotation marks (‘ ’). The Linux versions of the previous examples are:
-c ‘set storageArray userLabel="Engineering";’

Detailed Error Reporting

Error data collected from an error encountered by the CLI is written to a file. Detailed error reporting under the CLI works as follows:
• If the CLI must abnormally end execution or abort script command execution, error data is collected and saved before the CLI aborts.
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• The CLI automatically saves the error data by writing the data to a file with a standard name.
• The CLI does not have any provisions to avoid overwriting an existing version of the file containing error data.
For error processing, errors appear as two types:
• Parameter or syntax errors you might enter
• Exceptions that occur as a result of an operational error
When the CLI encounters either type of error, it writes information describing the error directly to the command line and sets a return code. Depending on the return code, the CLI might also write additional information about which parameter caused the error. The CLI also writes information about what command syntax was expected to help you identify any syntax errors you might have entered.
When an exception occurs while executing a command, the CLI automatically saves the error information to a file named excprpt.txt. The CLI attempts to place excprpt.txt in the directory specified by the system property devmgr.datadir, which by default is the "client/data" directory under the main installation directory in Windows and the /var/opt/SM directory in Linux. If for any reason the CLI cannot place the file in the devmgr.datadir-specified directory, the CLI saves the excprpt.txt file in the same directory from which the CLI is running. You cannot change the file name or location. The excprpt.txt file is overwritten every time an exception occurs. To save the information in the excprpt.txt file, you must copy the information to a new file or directory.

Exit Status

After you run a CLI command or a CLI and script command, status is displayed that indicates the success of the operation defined by the command. The status values are shown in the following table.
Table 3. Exit Status
Status Value Meaning
0 The command terminated without an error.
1 The command terminated with an error. Error information is also
displayed.
2 The script file does not exist.
3 An error occurred while opening an output file.
4 A storage array is not at the specified address.
5 Addresses specify different storage arrays.
6 A storage array name does not exist for the host agent connected.
7 The storage array name was not at the specified address.
8 The storage array name was not in the configuration file.
10 A management class does not exist for the storage array.
11 A storage array was not found in the configuration file.
12 An internal error occurred.
13 Invalid script syntax was found.
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Status Value Meaning
14 The RAID controller module was unable to communicate with the
storage array.
15 A duplicate argument was entered.
16 An execution error occurred.
17 A host was not at the specified address.
18 The World Wide Identifier (WWID) was not in the configuration file.
19 The WWID was not at the address.
20 An unknown IP address was specified.
21 The event monitor configuration file was corrupted.
22 The storage array was unable to communicate with the event
monitor.
23 The RAID controller module was unable to write alert settings.
24 The wrong management station was specified.
25 The command was not available.
26 The device was not in the configuration file.
27 An error occurred while updating the configuration file.
28 An unknown host error occurred.
29 The sender contact information file was not found.
30 The sender contact information file could not be read.
31 The userdata.txt file exists.
32 An invalid -I value in the e-mail alert notification was specified.
33 An invalid -f value in the e-mail alert notification was specified.

Usage Examples

The following examples show how to enter CLI commands on a command line. The examples show the syntax, form, and in some examples, script commands. Examples are shown for both Windows and Linux operating systems. The usage for the -c parameter varies depending on your operating system. On Windows operating systems, put quotation marks (" ") around the script command following the -c parameter. On Linux operating systems, put single quotation marks (‘ ’) around the script command following the -c parameter.
NOTE: See Script Commands for descriptions of the script commands used in the following examples.
This example shows how to change the name of a storage array. The original name of the storage array is Payroll_Array. The new name is Finance_Array.
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Windows:
SMcli -n "Payroll_Array" -c "set storageArray userLabel=\"Finance_Array\";"
Linux:
SMcli -n ‘Payroll_Array’ -c ‘set storageArray userLabel="Finance_Array";’
This example shows how to delete an existing virtual disk and create a new virtual disk on a storage array. The existing virtual disk name is Stocks_<_Bonds. The new virtual disk name is Finance. The RAID controller module host names are finance1 and finance2. The storage array is protected and requires the password TestArray.
Windows:
SMcli finance1 finance2 -c "set session password= \"TestArray\"; delete virtualDisk [\"Stocks_<_Bonds\"];create virtualDisk physicalDiskCount[3] raidLevel=5 capacity=10 GB userLabel=\"Finance\"; show storageArray healthStatus;"
Linux:
SMcli finance1 finance2 -c ‘set session password= delete virtualDisk ["Stocks_<_Bonds"]; create virtualDisk physicalDiskCount[3] raidLevel=5 capacity=10 GB userLabel="Finance"; show storageArray healthStatus;’
This example shows how to run commands in a script file named scriptfile.scr on a storage array named Example. The -e parameter runs the file without checking syntax. Executing an SMcli command without checking syntax enables the file to run more quickly; however, the correctly if the syntax is incorrect.
SMcli -n Example -f scriptfile.scr -e
SMcli command may not execute
This example shows how to run commands in a script file named scriptfile.scr on a storage array named Example. In this example, the storage array is protected by the password My_Array. Output, as a result of commands in the script file, goes to file output.txt.
Windows:
SMcli -n Example -f scriptfile.scr -p "My_Array" - o output.txt
Linux:
SMcli -n Example -f scriptfile.scr -p ‘My_Array’ - o output.txt
This example shows how to display all storage arrays that are currently discovered in the current configuration. The command in this example returns the host name of each storage array.
SMcli -d
If you want to know the IP address of each storage array in the configuration, add the -i parameter to the command.
SMcli -d -i
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3

About The Script Commands

You can use the script commands to configure and manage a storage array. The script commands are distinct from the command line interface (CLI) commands; however, you enter the script commands using the command line interface. You can enter individual script commands, or run a file of script commands. When entering an individual script command, include it as part of a CLI command. When running a file of script commands, include the file name as part of a CLI command. The script commands are processed by a script engine that performs the following functions:
• Verifies command syntax
• Interprets the commands
• Converts the commands to the appropriate protocol-compliant commands, which is, in turn, run by the RAID controller module
• Passes the commands to the storage array
At the storage array, the redundant array of independent disks (RAID) controller modules in the storage array runs the script commands.
The script engine and script commands support the storage array configuration and management operations listed in the following table.
Table 4. Configuration and Management Operations
Operation Activities
Virtual disk, disk group configuration Creating, deleting, and setting priority; labeling;
setting physical disk composition when creating virtual disks; setting segment size; and setting media scan control
Physical disk configuration Configuring the hot spare
RAID controller module configuration Defining virtual disk ownership, changing mode
settings, defining network settings, and setting host port IDs
General storage array configuration Resetting a configuration to defaults, labeling,
checking the health status, setting the time of day, clearing the Major Event Log, and setting the media scan rate
NVSRAM configuration Downloading and modifying the user configuration
region at the bit and byte level, displaying nonvolatile static random access memory (NVSRAM) values
Product identification Retrieving the enclosure profile display data
Battery management Setting the battery installation date
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Operation Activities
Firmware management Downloading RAID controller module, enclosure
management module (EMM), and physical disk firmware

Script Command Structure

All script commands have the following structure:
command operand-data {statement-data}
where, command identifies the action to be performed, operand-data represents the storage array component to configure or manage (such as a RAID controller module, physical disk, or disk group), and statement-data is what you want to do to the component (such as, specifying the RAID level or availability of a disk group).
The general form of the syntax for operand-data is as follows:
(object-type | allobject-types | [qualifier] (object-type [identifier] {object-type [identifier]} | object-types [identifier-list]))
An operand-data object can be identified four ways:
• The object types and object qualifiers
• The all parameter
• Brackets
• A list of identifiers
NOTE: You can use any combination of alphanumeric characters, hyphens, and underscores for the names. Command names can have a maximum of 30 characters. If you exceed the maximum character limit, replace square brackets ([ ]) with angle brackets (< >) to overcome this limitation.
Use an object type when the command is not referencing a specific object. The all parameter means all objects of the specified type in the storage array (for example,
To perform a command on a specific object, use brackets to identify the object (for example,
virtualDisk[engineering]). Specify a subset of objects with a list of identifiers in brackets (for example, virtualDisks[sales engineering marketing]). In a list of identifiers, use a blank space as the delimiter. A
qualifier is necessary if you want to include additional information to describe the objects.
The following table lists the object type and identifiers associated with the object types.
Table 5. Object Types and Identifiers
Object Type Identifier
controller 0 or 1
physicalDisk Enclosure ID and the slot ID
physicalDiskChannel Physical disk channel identifier
GroupName Remote Replication virtual disk user label
allVirtualDisks).
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Object Type Identifier
host User label
hostChannel Host channel identifier
hostGroup User label
hostPort User label
snapVirtualDiskName Virtual disk user label
snapshot Virtual disk user label
snapGroup A snapshot group contains a sequence of snapshot
images of an associated base virtual disk. A snapshot group has a repository virtual disk that is used to save data for all of the snapshot images that are part of the snapshot group.
snapGroupName Virtual disk group user label
storageArray Not applicable
enclosure Enclosure ID
virtualDisk Virtual disk user label or the World Wide Identifier
(WWID) for the virtual disk (set command only)
virtualDiskCopy Target virtual disk and, optionally, the source virtual
disk user labels
diskGroup Virtual disk group number
Statement data is in the form of attribute=value (such as raidLevel=5), an attribute name (such as
batteryInstallDate), or an operation name (such as consistencyCheck).

Script Command Synopsis

Because you can use the script commands to define and manage the different aspects of a storage array (such as host topology, physical disk configuration, RAID controller module configuration, virtual disk definitions, and disk group definitions), the actual number of commands is extensive. The commands, however, fall into general categories that are reused when you apply the commands to the different aspects of a storage array.
The following table lists the general form of the script commands and provides a definition of each command.
Table 6. General Form of the Script Commands
Command Syntax Description
activate object {statement‑data} Sets up the environment so that an operation can
take place or performs the operation if the environment is already correctly set up.
autoConfigure storageArray{statement-data} Automatically creates a configuration based on
parameters specified in the command.
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Command Syntax Description
check object {statement‑data} Starts a synchronous operation to report on errors
in the object.
clear object {statement‑data} Discards the contents of some attribute of an
object. This is a destructive operation that cannot be reversed.
create object {statement‑data} Creates an object of the specified type.
deactivate object {statement‑data} Removes the environment for an operation.
delete object Deletes a previously created object.
diagnose object {statement‑data} Runs a test and displays the results.
disable object {statement‑data} Prevents a feature from operating.
download object {statement‑data} Transfers data to the storage array or hardware
associated with the storage array.
enable object {statement‑data} Allows a feature to operate.
recopy object {statement‑data} Restarts a virtual disk copy operation by using an
existing virtual disk copy pair. You can change attributes before the operation is restarted.
recover object {statement‑data} Re-creates an object from saved configuration
data and the statement attributes (similar to the create command).
recreate object {statement‑data} Restarts a snapshot operation using an existing
snapshot virtual disk. You can change attributes before the operation is restarted.
remove object {statement‑data} Removes a relationship from between objects.
repair object {statement‑data} Repairs errors found by the check command.
reset object {statement‑data} Returns the hardware or object to an initial state.
resume object Starts a suspended operation. The operation
begins where it left off when suspended.
revive object Forces the object from the Failed to the Optimal
state. Use only as part of an error recovery procedure.
save object {statement‑data} Writes information about the object to a file.
set object {statement‑data} Changes object attributes. All changes are
completed when the command returns.
show object {statement‑data} Displays information about the object.
start object {statement‑data} Starts an asynchronous operation. You can stop
some operations after they have started. You can query the progress of some operations.
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Command Syntax Description
stop object {statement‑data} Stops an asynchronous operation.
suspend object {statement‑data} Suspends an operation. You can then restart the
suspended operation, and it continues from the point at which it was suspended.

Recurring Syntax Elements

Recurring syntax elements are a general category of variables and parameters you can use in one or more script commands. The recurring syntax is used in the general definitions of the script commands that are listed in Script Commands. The following table lists the recurring syntax and the syntax values that you can use with the syntax.
Table 7. Recurring Syntax Elements
Recurring Syntax Syntax Value
raid-level (0 | 1 | 5| 6)
snapshot-repository-raid-level (1 | 5 | 6)
capacity-spec integer-literal [KB | MB | GB | TB | Bytes]
segment-size-spec integer-literal
boolean (TRUE | FALSE)
user-label string-literal
user-label-list user-label {user-label}
create-raid-vol-attr-value-list create-raid-virtual disk-attribute-valuepair
{create-raid-virtual disk-attribute-valuepair}
create-raid-virtual disk-attribute-value-pair capacity=capacity-spec | owner=(0 | 1) |
segmentSize=integer-literal
RAID controller module-enclosureId (0–99)
slot-id (0–31)
port-id (0–127)
physical disk-spec enclosureID, slotID
physical disk-spec-list physical disk-spec {physical disk-spec}
enclosure-id-list enclosureID {enclosureID}
hex-literal 0x hexadecimal-literal
virtual disk-group-number integer-literal
filename string-literal
error-action (stop | continue)
physical disk-channel-identifier (1 | 2)
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Recurring Syntax Syntax Value
physical disk-channel-identifier-list physical disk-channel-identifier {physical disk-
channel-identifier}
host-channel-identifier (01 | 02 | 11 | 12)
physical disk-type (Serial Attached SCSI [SAS])
feature-identifier (snapshot | virtualDiskCopy)
repository-spec instance-based-repository-spec | count-based-
repository-spec
ethernet-port-options IPV4Address=ipv4-address|
IPV4ConfigurationMethod=[(static | dhcp)] |
IPV4GatewayIP=ipv4-address|
IPV4SubnetMask=ipv4-address|
iscsi-host-port-options IPV4Address=ipv4-address |
IPV6LocalAddress=ipv6-address |
IPV6RoutableAddress=ipv6-address |
IPV6RouterAddress=ipv6-address |
enableIPV4= boolean |
enableIPV6=boolean |
enableIPV4Vlan=boolean |
enableIPV6Vlan=boolean |
enableIPV6Priority=boolean |
enableIPV6Priority=boolean |
IPV4ConfigurationMethod=(static | dhcp) |
IPV6ConfigurationMethod=(static | auto) |
IPV4GatewayIP= ipv4-address |
IPV6HopLimit=integer |
IPV6NdDetectDuplicateAddress= integer |
IPV6NdReachableTime=integer |
IPV6NdRetransmitTime=integer |
IPV6NdTimeOut=integer |
IPV4Priority=integer |
IPV6Priority=integer |
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Recurring Syntax Syntax Value
IPV4SubnetMask=ipv4-address |
IPV4VlanID=integer |
IPV6VlanID=integer |
maxFramePayload=integer |
tcpListeningPort=tcp-port-id|
NOTE: You must set the enableIPV4 parameter or the enableIPV6 parameter to TRUE to ensure that the specific IPV4 or IPV6 setting is applied.
NOTE: The IPV6 address space is 128 bits. It is represented by eight 16-bit hexadecimal blocks separated by colons. You may drop leading zeros, and use a double colon to represent consecutive blocks of zeroes.
instance-based-repository-spec
repositoryRAIDLevel=repository-raidlevel
repositoryPhysicalDisks=(physical diskspec- list)
[enclosureLossProtect=boolean] repositoryDiskGroup=virtual-diskgroup- number [freeCapacityArea=integer-literal]
Specify repositoryRAIDLevel with repositoryPhysicalDisks. Do not specify RAID level or physical disks with a disk group. Do not set a disk group.
enclosureLossProtect when specifying
NOTE: For enclosure loss protection to work, each physical disk in a disk group must be on a separate enclosure. If you set enclosureLossProtect=TRUE and have selected more than one physical disk from any one enclosure, the storage array returns an error. If you set enclosureLossProtect=FALSE, the storage array performs operations, but the disk group you create might not have enclosure loss protection.
NOTE: To determine if a free capacity area exists, issue the show diskGroup command.
count-based-repository-spec
repositoryRAIDLevel=repository-raidlevel
repositoryPhysicalDiskCount=integerliteral
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Recurring Syntax Syntax Value
[physicalDiskType=physical disk-type]
[enclosureLossProtect=boolean]
WWID
nvsram-offset hexadecimal-literal
host-type string-literal | integer-literal
nvsram-byte-setting nvsram-value
nvsram-bit-setting nvsram-mask, nvsram-value
ipv4-address (0–255).(0–255).(0–255).(0–255)
ipv6-address (0-FFFF):(0-FFFF):(0-FFFF):
autoconfigure-vols-attr-value-list autoconfigure-vols-attr-value-pair
autoconfigure-vols-attr-value-pair physicalDiskType=physical disk-type|
string-literal
For hostPort identifiers this is a 16-digit hex number without any colon delimiters.
(0x hexadecimal | integer-literal)
(0x hexadecimal, 0x hexadecimal | integer-literal)
(0-FFFF):(0-FFFF):(0-FFFF):
(0-FFFF):(0-FFF)
{autoconfigure-vols-attr-value-pair}
raidLevel=raid-level |
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diskGroupWidth=integer-literal |
diskGroupCount=integer-literal |
virtualDisksPerGroupCount=integerliteral|
hotSpareCount=integer-literal |
segmentSize=segment-size-spec
NOTE: The physicalDiskType parameter is not required if only one type of physical disk is in the storage array. If you use the physicalDiskType parameter, you must also use the hotSpareCount and diskGroupWidth parameters. If you do not use the physicalDiskType parameter, the configuration defaults to SAS physical disks.
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Recurring Syntax Syntax Value
NOTE: The virtualDisksPerGroupCount parameter is the number of equal capacity virtual disks per disk group.
create-virtual-disk-copy-attr-value-list create-virtual-disk-copy-attr-value-pair
{create-virtual-disk-copy-attr-value-pair}
create-virtual-disk-copy-attr-value-pair copyPriority=highest | high | medium | low | lowest
| targetReadOnlyEnabled=boolean
recover-raid-virtual-disk-attr-value-list recover-raid-virtual-disk-attr-value-pair
{recover-raid-virtual-disk-attr-value-pair}
recover-raid-virtual-disk-attr-value-pair owner=(0 | 1)
Table 8. Range of Values for Recurring Syntax Elements
Recurring Syntax Syntax Values
IPV4Priority 0 to 7
IPV4VlanID 1 to 4094
IPV6Priority 0 to 7
IPV6VlanID 1 to 4094
IPV6HopLimit 0 to 255 (default value is 64)
IPV6NdDetectDuplicateAddress 0 to 256
IPV6NdReachableTime 0 to 65535 (default value is 30000 milliseconds)
IPV6RetransmitTime 0 to 65535 (default value is 1000 milliseconds)
IPV6NDTimeOut 0 to 65535 (default value is 3000 milliseconds)
maxFramePayload 1500
NOTE: The maxFramePayload parameter is shared between IPv4 and IPv6. The payload portion of a standard Ethernet frame is set at 1500 bytes, and a jumbo Ethernet frame is set at 9000 bytes. When using jumbo frames, make sure that all of the devices contained in the network path can handle the larger frame size.
tcpListeningPort (tcp-port-id) 3260, or 49,152 to 65,536
The default value is 3260.
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Usage Guidelines

The following list provides guidelines for writing script commands on the command line:
• You must end all commands with a semicolon (;).
• You can enter more than one command on a line, but you must separate each command with a semicolon (;).
• You must separate each base command and its associated primary and secondary parameters with a space.
• The script engine is case sensitive.
• You can add comments to your scripts to make it easier for you and future users to understand the purpose of the script commands. For information on how to add comments, see Adding Comments To A Script File.
NOTE: User labels (such as for virtual disk, hosts, or host ports) are case sensitive. If you map to an object identified by a user label, you must enter the user label exactly as it is defined, or the CLI and script commands fails.
NOTE: You can use any combination of alphanumeric characters, hyphens, and underscores for the names. Command names can have a maximum of 30 characters. If you exceed the maximum character limit, replace square brackets ([ ]) with angle brackets (< >) to overcome this limitation.
NOTE: The capacity parameter returns an error if you specify a value greater than or equal to 10 without a space separating the numeric value and its unit of measure. For example, 10 GB returns an error, but
9 GB does not return an error.

Adding Comments To A Script File

You can add comments to a script file in three ways:
• The script engine interprets as a comment any text typed after two forward slashes (/ /) until an end‑of‑line character is reached. If the script engine does not find an end‑of‑line character in the script after processing a comment, an error message is displayed, and the script operation is terminated. This error commonly occurs when a comment is placed at the end of a script and you have not pressed <Enter>.
// Deletes the existing configuration. clear storageArray Configuration;
• The script engine interprets any text typed between / * and * / as a comment. If the script engine does not find both a beginning and ending comment notation, an error message is displayed, and the script operation is terminated.
/* Deletes the existing configuration */ clear storageArray Configuration;
• Use the show statement to embed comments in a script file that you want to display while the script file is running. Enclose the text you want to display in quotation marks (" ").
show "Deletes the existing configuration"; clear storageArray Configuration;
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4

Configuring A Storage Array

This chapter explains how to run script commands from the command line to create a virtual disk from a group of physical disks, and how to configure a redundant array of independent disks (RAID) storage array. This chapter assumes that you understand basic RAID concepts and terminology. Before configuring the storage array, become familiar with the concepts of physical disks, disk groups, virtual disks, host groups, hosts, and RAID controller modules. Additional information about configuring a storage array and related definitions is in the online help, the Deployment Guide, the MD Storage Manager online help, and the Owner’s Manual.
Configuring a RAID storage array requires caution and planning to ensure that you define the correct RAID level and configuration for your storage array. The main purpose in configuring a storage array is to create virtual disks addressable by the hosts from a collection of physical disks. The commands described in this chapter enable you to set up and run a RAID storage array. Additional commands are also available to provide more control and flexibility. Many of these commands, however, require a deeper understanding of the firmware as well as various structures that need to be mapped. Use all the command line interface (CLI) commands and script commands with caution.
The following sections in this chapter show some, but not all, of the CLI and script commands. The purpose of showing these commands is to explain how you can use the commands to configure a storage array. The presentation in this chapter does not explain all possible usage and syntax for the commands. For complete definitions of the commands, including syntax, parameters, and usage notes, see Script Commands.
This chapter contains examples of CLI and script command usage. The command syntax used in the examples is for a host running a Microsoft Windows operating system. As part of the examples, the complete C:\ prompt and DOS path for the commands are shown. Depending on your operating system, the prompt and path construct varies.
For most commands, the syntax is the same for all Windows and Linux operating systems, as well as for a script file. Windows operating systems, however, have an additional requirement when entering names in a command. On Windows, you must enclose the name between two backslashes (\) in addition to other delimiters. For example, the following name is used in a command that runs under Windows:
[\"Engineering\"]
For a Linux system when used in a script file, the name appears as:
["Engineering"]
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Configuring A Storage Array

When you configure a storage array, you can maximize data availability by ensuring that data is quickly accessible while maintaining the highest level of data protection possible. The speed at which a host can access data is affected by the disk group RAID level and the segment size settings. Data protection is determined by the RAID level, hardware redundancy (such as global hot spares), and software redundancy (such as the Snapshot feature).
In general, you configure a storage array by defining the following entities:
• A disk group and associated RAID level
• The virtual disks
• Which hosts have access to the virtual disks
This section explains how to use the script commands to create a configuration from an array of physical disks.

Determining What Is On Your Storage Array

Even when you create a configuration on a previously unconfigured storage array, you still need to determine the hardware and software features that must be included with the storage array. When you configure a storage array with an existing configuration, you must ensure that your new configuration does not inadvertently alter the existing configuration, unless you are reconfiguring the entire storage array. For example, to create a new disk group on unassigned physical disks, you must determine which physical disks are available. The commands described in this section enable you to determine the components and features in your storage array.
The show storageArray command returns the following general information about the components and properties of the storage array:
• A detailed profile of the components and features in the storage array
• The battery age
• The default host type (which is the current host type)
• Other available host types
• The hot spare locations
• The identifiers for enabled features
• The logical and physical component profiles
• The time to which both RAID controller modules are set
• The RAID controller module that currently owns each virtual disk in the storage array
To return the most information about the storage array, run the show storageArray command with
profile parameter. The following is an example of the complete CLI and script command running
the on Windows:
client>smcli 123.45.67.89 -c "show storageArray profile;"
This example identifies the storage array by the dummy IP address 123.45.67.89. You can also identify the storage array by name.
The show storageArray profile command returns detailed information about the storage array. The information is presented in several screens on a display. You might need to increase the size of your
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display buffer to see all of the information. Because this information is so detailed, you might want to save the output to a file. To save the output to a file, enter the command as shown in the following example:
client>smcli 123.45.67.89 -c "show storageArray profile;"
-o c:\folder\storageArrayprofile.txt
In this example, the name folder is the folder in which you choose to place the profile file, and storageArrayprofile.txt is the name of the file. You can choose any folder and any file name.
CAUTION: When you write information to a file, the script engine does not check to determine if the file name already exists. If you choose the name of a file that already exists, the script engine writes over the information in the file without warning.
When you save the information to a file, you can use the information as a record of your configuration and as an aid during recovery.
To return a brief list of the storage array features and components, use the summary parameter. The command is similar to the following example:
client>smcli 123.45.67.89 -c "show storageArray summary;"
The summary information is also returned as the first section of information when you use the profile parameter.
The following show commands return information about the specific components of a storage array. The information returned by each of these commands is the same as the information returned by the show storageArray profile command, but is constrained to the specific component.
NOTE: The following commands are not complete commands. For information about a command, see the referenced section next to the command.
• show controller (RAID Controller Module Commands)
• show physicalDisks (Show Physical Disk)
• show physicalDiskchannels stats (Show Physical Disk Channel Statistics)
• show storageArray hostTopology (Show Storage Array Host Topology)
• show storageArray lunmappings (Show Storage Array LUN Mappings)
• show allVirtualDisks (Show Virtual Disk)
• show diskGroup (Show Disk Group)
• show virtualDisk reservations (Show Virtual Disk Reservations)
The following commands also return information about a storage array:
• show storageArray autoConfigure (Show Storage Array Auto Configure)
• show controller NVSRAM (Show RAID Controller Module NVSRAM)
• show storageArray unreadableSectors (Show Storage Array Unreadable Sectors)
• show virtualDiskCopy sourceCandidates (Show Virtual Disk Copy Source Candidates)
• show virtualDiskCopy targetCandidates (Show Virtual Disk Copy Target Candidates)
• show virtualDisk performanceStat (Show Disk Group Import Dependencies)
For descriptions of the show commands, including examples of the information returned by each command, see Script Commands. Other commands can help you learn about your storage array. To see a list of the commands, see Commands Listed By Function. These commands are organized by the
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storage array activities that the commands support. Examples include virtual disk commands, host commands, enclosure commands, and others.

Saving A Configuration To A File

CAUTION: When you write information to a file, the script engine does not check to determine if the file name already exists. If you choose the name of a file that already exists, the script engine writes over the information in the file without warning.
After you have created a new configuration or if you want to copy an existing configuration for use on other storage arrays, you can save the configuration to a file. To save the configuration, use the save storageArray configuration command. Saving the configuration creates a script file that you can run on the command line. The following syntax is the general form of the command:
save storageArray configuration file="filename" [(allconfig | globalSettings=(TRUE | FALSE)) | virtualDiskConfigAndSettings=(TRUE | FALSE) | hostTopology=(TRUE | FALSE) | lunMappings=(TRUE | FALSE)]
You can choose to save the entire configuration or specific configuration features. The command for setting this parameter value looks like the following example:
client>smcli 123.45.67.89 -c "save storageArray configuration file= \"c:\folder\storageArrayconfig1.scr\";"
In this example, the name folder is the folder in which you choose to place the configuration file, and storageArrayconfig1.scr is the name of the file. Choose any folder and any file name. MD Storage Manager uses the file extension .scr when it creates the configuration file.

Using The Create Virtual Disk Command

The create virtualDisk command enables you to create new virtual disks in the storage array in three ways:
• Create a new virtual disk while simultaneously creating a new disk group to which you assign the physical disks.
• Create a new virtual disk while simultaneously creating a new disk group to which the MD Storage Manager software assigns the physical disks.
• Create a new virtual disk in an existing disk group.
You must have unassigned physical disks in the disk group. You do not need to assign the entire capacity of the disk group to a virtual disk.
Creating Virtual Disks With User-Assigned Physical Disks
When you create a new virtual disk and assign the physical disks to use, the MD Storage Manager software creates a new disk group. The RAID controller module firmware assigns a disk group number to the new disk group. The following syntax is the general form of the command:
create virtualDisk physicalDisks= (enclosureID0,slotID0...enclosureIDn,slotIDn) raidLevel=(0 | 1 | 5 | 6)userLabel= "virtualDiskName" [capacity=virtualDiskCapacity owner=(0 | 1) segmentSize=segmentSizeValue] [enclosureLossProtect=(TRUE | FALSE)]
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NOTE: The capacity, owner, segmentSize, and enclosureLossProtect parameters are optional. You can use one or all of the optional parameters as needed to help define your configuration. You do not, however, need to use any optional parameters.
The userLabel parameter is the name to give to the virtual disk. The virtual disk name can be any combination of alphanumeric characters, hyphens, and underscores. The maximum length of the virtual disk name is 30 characters. Spaces are not allowed. You must put quotation marks (" ") around the virtual disk name.
The physicalDisks parameter is a list of the physical disks that you want to use for the disk group. Enter the enclosure ID and slot ID of each physical disk that you want to use. Put parentheses around the list. Separate the enclosure ID and slot ID of a physical disk by a comma. Separate each enclosure ID and slot ID pair by a space. For example:
(0,0 0,1 0,2 0,3 0,4)
The capacity parameter defines the size of the virtual disk. You do not have to assign the entire capacity of the physical disks to the virtual disk. You can later assign any unused space to another virtual disk.
The owner parameter defines the RAID controller module to which you want to assign the virtual disk. If you do not specify a RAID controller module, the RAID controller module firmware determines the owner of the virtual disk.
The segmentSize parameter is the same as described for the autoConfigure storageArray command. See Using The Auto Configure Command.
The enclosureLossProtect parameter turns on or turns off enclosure loss protection for the disk group. For a description of how enclosure loss protection works, see Enclosure Loss Protection.
Example Of Creating Virtual Disks With User-Assigned Physical Disks
client>smcli 123.45.67.89 -c "create virtualDisk physicalDisks=(0,0 0,1 0,2) raidLevel=5 userLabel= \"Engineering_1\" capacity=20 GB owner=0;"
NOTE: The capacity parameter returns an error if you specify a value greater than or equal to 10 without a space separating the numeric value and its unit of measure. (For example, 10 GB returns an error, but 10 GB does not return an error).
The command in this example automatically creates a new disk group and a virtual disk with the name Engineering_1. The disk group has a RAID level of 5 (RAID 5). The command uses three physical disks to construct the disk group. The virtual disk created has a capacity of 20 GB. If each physical disk has a capacity of 73 GB, the total capacity of the disk group is 219 GB.
Because only 20 GB are assigned to the virtual disk, 199 GB remain available for other virtual disks that you can later add to this disk group. The segment size for each virtual disk is 64 KB. Hot spares have not been created for this new disk group. You must create hot spares after running this command.
Creating Virtual Disks With Software-Assigned Physical Disks
You can let the MD Storage Manager software assign the physical disks when you create the virtual disk. To have the software assign the physical disks, only specify the number of physical disks to use. The MD Storage Manager software then chooses the physical disks on which the virtual disk is created. The RAID
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controller module firmware assigns a disk group number to the new disk group. The following syntax is the general form for the command:
create virtualDisk physicalDiskCount= numberOfPhysicalDisks raidLevel=(0 | 1 | 5 | 6) userLabel="virtualDiskName" [physicalDiskType= (SAS)] [capacity=virtualDiskCapacity | owner=(0 |
1) | segmentSize=segmentSizeValue]
[enclosureLossProtect=(TRUE | FALSE)])
NOTE: The physicalDiskType, capacity, owner, segmentSize, and enclosureLossProtect parameters are optional. You can use one or all of the optional parameters as needed to help define your configuration. You do not, however, need to use any optional parameters.
This command is similar to the previous create virtualDisk command, which allows the user to assign the physical disks. This version of the command requires only the number and the type of physical disks to use in the disk group. You do not need to enter a list of physical disks. All other parameters are the same. Enclosure loss protection is performed differently when MD Storage Manager assigns the physical disks as opposed to when a user assigns the physical disks. For an explanation of the difference, see Enclosure Loss Protection.
Example Of Creating Virtual Disks With Software-Assigned Physical Disks
client>smcli 123.45.67.89 -c "create virtualDisk physicalDiskCount=3 raidLevel=5 userLabel= \"Engineering_1"\ capacity=20 GB owner=0 segmentSize=64;"
The command in this example creates the same virtual disk as the previous create virtualDisk command. However, in this case the user does not know which physical disks are assigned to this disk group.
Creating Virtual Disks In An Existing Disk Group
To add a new virtual disk to an existing disk group, use the following command:
create virtualDisk DiskGroup=diskGroupNumber userLabel="virtualDiskName" [freeCapacityArea= freeCapacityIndexNumber | capacity= virtualDiskCapacity | owner=(0 | 1) | segmentSize= segmentSizeValue]
NOTE: The freeCapacityArea, capacity, owner, and segmentSize parameters are optional. You can use one or all optional parameters as needed to help define your configuration, though you do not need to use any of them.
The diskGroup parameter is the number of the disk group in which you want to create a new virtual disk. If you do not know the disk group numbers on the storage array, you can use the allVirtualDisks summary command. This command displays a list of the virtual disks and the disk groups to which the virtual disks belong.
The userLabel parameter is the name you want to give to the virtual disk. The virtual disk name can be any combination of alphanumeric characters, hyphens, and underscores. The maximum length of the virtual disk name is 30 characters. You must enclose the virtual disk name with quotation marks (" ").
The freeCapacityArea parameter defines the free capacity area to use for the virtual disk. If a disk group has several free capacity areas, you can use this parameter to identify which free capacity area to
show
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use for virtual disk creation. You do not have to assign the entire capacity of the physical disks to the virtual disk. Assign any unused space to another virtual disk at another time.
The userLabel, capacity, owner, and segmentSize parameters are the same as in the previous versions of the create virtualDisk command.
Enclosure Loss Protection
The enclosureLossProtect parameter is a boolean switch that turns enclosure loss protection on or off. To work properly, each physical disk in a virtual disk group must be in a separate enclosure. Enclosure loss protection is set under the following conditions:
• You assign the physical disks.
• The RAID controller module assigns the physical disks.
The following table shows possible results for the enclosureLossProtect parameter. The results depend on whether you assign the physical disks or the RAID controller module assigns the physical disks.
Method enclosureLossProtect= TRUE enclosureLossProtect=FALSE
You assign the physical disks. If you select more than one
physical disk from any one enclosure, the storage array returns an error.
The RAID controller module firmware assigns the physical disks.
The enclosureLossProtect parameter is not valid when creating virtual disks on existing disk groups.
The storage array posts an error if the RAID controller module firmware cannot provide physical disks to ensure that the new disk group has enclosure loss protection.
The storage array performs the operation, but the created disk group does not have enclosure loss protection.
The storage array performs the operation even if it means that the disk group might not have enclosure loss protection.

Using The Auto Configure Command

The autoConfigure storageArray command creates the disk groups on a storage array, the virtual disks in the disk groups, and the hot spares for the storage array. When you use the autoConfigure storageArray command, define the following parameters:
• Type of physical disks (Serial Attached SCSI [SAS])
• RAID level
• Number of physical disks in a disk group
• Number of disk groups
• Number of virtual disks in each disk group
• Number of hot spares
• Size of each segment on the physical disks
After defining these parameters, the MD Storage Manager automatically creates the disk groups, virtual disks, and hot spares. The RAID controller modules assign disk group and virtual disk numbers as they are created. After MD Storage Manager creates the initial configuration, you can use the set virtualDisk command to define virtual disk labels.
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Before running the autoConfigure storageArray command, run the show storageArray autoConfigure command. The show storageArray autoConfigure command returns a list of parameter values that MD Storage Manager uses to create a storage array. Change any of the parameter values by entering new values for the parameters when you run the command. If you are satisfied with the parameter values that the show storageArray
autoConfiguration
new parameter values.
The following syntax is the general form of autoConfigure storageArray command:
autoConfigure storageArray [physicalDiskType= (SAS) raidLevel=(0 | 1 | 5 | 6) | diskGroupWidth= numberOfPhysicalDisks | diskGroupCount= numberOfDiskGroups | virtualDisksPerGroupCount= numberOfVirtualDisksPerGroup | hotSpareCount= numberOfHotspares | segmentSize=segmentSizeValue]
NOTE: All parameters are optional. You can use one or all of the parameters as needed to define your configuration.
When you use the autoConfigure storageArray command without specifying the number of disk groups, the firmware determines how many virtual disks and disk groups to create. The firmware creates one disk group and one virtual disk up to the maximum number that the storage array can support. When you specify the number of disk groups, the firmware creates only that number of disk groups. When you create more than one disk group, all of the disk groups have the same number of physical disks and the same number of virtual disks.
command returns, run the autoConfigure storageArray command without
autoConfigure storageArray
• The diskGroupWidth parameter defines the number of unassigned physical disks wanted for each new disk group.
• The diskGroupCount parameter defines the number of new disk groups wanted in the storage array.
• The virtualDisksPerGroupCount parameter defines the number of virtual disks wanted in each disk group.
• The hotSpareCount parameter defines the number of hot spares wanted in each disk group.
• The segmentSize parameter defines the amount of data in kilobytes that the RAID controller module writes on a single physical disk in a virtual disk before writing data on the next physical disk. The smallest units of storage are data blocks. Each data block stores 512 bytes of data. The size of a segment determines how many data blocks that it contains. An 8-KB segment holds 16 data blocks. A 64-KB segment holds 128 data blocks.
Valid values for the segment size are 8, 16, 32, 64, 128, 256, and 512.
When you enter a value for the segment size, the value is checked against the supported values provided by the RAID controller module at run time. If the value you enter is not valid, the RAID controller module returns a list of valid values.
If the virtual disk is for a single user with large I/O requests (such as multimedia), performance is maximized when a single I/O request can be serviced with a single data stripe. A data stripe is the segment size multiplied by the number of physical disks in the disk group that are used for data storage. In this environment, multiple physical disks are used for the same request, but each physical disk is accessed only once.
For optimal performance in a multi-user database or file system storage environment, set the segment size to minimize the number of physical disks needed to satisfy an I/O request. Using a single physical disk for a single request leaves other physical disks available to simultaneously service other requests.
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After you have finished creating the disk groups and virtual disks by using the autoConfigure storageArray command, you can further define the properties of the virtual disks in a configuration using the
Example Of The Auto Configuration Command
client>smcli 123.45.67.89 -c "autoConfigure storageArray physicalDiskType=SAS raidLevel=5 diskGroupWidth=8 diskGroupCount=3 virtualDisksPerGroupCount=4 hotSpareCount=2 segmentSize=8;"
The command in this example creates a storage array configuration that uses SAS physical disks set to RAID level 5. Three disk groups are created. Each disk group consists of eight physical disks configured into four virtual disks. The storage array has two hot spares, and segment size for each virtual disk is 8 KB.
set virtualDisk command. (See Modifying Your Configuration.)

Modifying Your Configuration

After creating your initial configuration, modify the properties of the configuration to ensure that it meets your requirements for data storage. Use the following commands to modify the properties of your configuration:
• autoConfigure storageArray
• create virtualDisk
Use the set commands to modify a storage array configuration. This section explains how to modify the following properties:
• Storage array password
• Simple Mail Transport Protocol (SMTP) and Simple Network Management Protocol (SNMP) alerts
• RAID controller module clocks
• Storage array host type
• Global hot spares
NOTE: Before modifying your configuration, save a copy of your current configuration to a file (see Saving A Configuration To A File). If you have problems with your modifications, you can use the information in the file to restore your previous configuration.

Setting The Storage Array Password

The set storageArray command enables you to define a password for a storage array. The following syntax is the general form of the command:
set storageArray password="password"
The password parameter defines a password for the storage array. Passwords provide added security to a storage array to reduce the possibility of implementing destructive commands.
CAUTION: Implementing destructive commands can cause serious damage, including data loss.
NOTE: CLI commands do not have interactive warnings for destructive commands.
Unless you define a password for the storage array, anyone can run all of the script commands. A password protects the storage array from any command that the RAID controller modules consider destructive. A destructive command is any command that can change the state of the storage array, such
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as virtual disk creation, reset, delete, rename, or change. If you have more than one storage array in a storage configuration, each array has a separate password. Passwords can have a maximum length of 30 characters. You must put quotation marks (" ") around the password. The following example shows how to use the set storageArray command to define a password:
client>smcli 123.45.67.89 -c "set storageArray password=\"1a2b3c4d5e"\;"

Setting Up SMTP And SNMP Alerts

The storage array can be set up to send automatic e-mail alert messages to specified email addresses when specific events occur. View the current alert configuration settings using the following command:
SMcli -d -i -s -w -v -S
By default, all alert configuration settings are None.
The following example shows how to set the mail server IP and the sender address configurations for SMTP alerts:
SMcli -m 123.45.67.892 -F MyStorageArrayEvent@MyCompany.com
or
SMcli -m MyCompany.com -F MyStorageArrayEvent@MyCompany.com
An example of a command to set the email alert destination and specify that only event information is to be sent is:
SMcli -a email:MyCompanySupport@MyCompany.com
123.45.67.89 -I eventOnly
The following example shows how to set the SNMP trap alert configuration. In this example, the trap destination is 123.45.67.891. The storage array is 123.45.67.892, and the community name is public.
SMcli -a trap:public, 123.45.67.891 123.45.67.892

Setting The RAID Controller Module Clocks

To synchronize the clocks on the RAID controller modules with the host, use the set storageArray time command. Running this command helps ensure that event timestamps written by RAID controller
modules to the Major Event Log (MEL) match event timestamps written to the host log files. The RAID controller modules remain available during synchronization. An example of the command is:
client>smcli 123.45.67.89 -c "set storageArray time;"

Setting The Storage Array Host Type

The set storageArray command enables you to define the default host type. The following syntax is the general form of the command:
set storageArray defaultHostType=(hostTypeName | hostTypeIdentifier)
The defaultHostType parameter defines how the RAID controller modules communicate with the operating system on undefined hosts connected to the storage array. This parameter defines the host type only for storage array data I/O activities; it does not define the host type for the management station. The operating system can be Windows or Linux. For example, if you set the defaultHostType to Linux, the RAID controller module communicates with any undefined host if the undefined host is
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running Linux. Typically, you need to change the host type only when you are setting up the storage array. The only time you might need to use this parameter is if you need to change how the storage array behaves relative to the hosts.
Before you can define the default host type, you need to determine what host types are connected to the storage array. To return information about host types connected to the storage array, you can use the show storageArray command with the defaultHostType parameter or hostTypeTable parameter. This command returns a list of the host types with which the RAID controller modules can communicate; it does not return a list of the hosts. The following examples show how to use the defaultHostType parameter and the hostTypeTable parameter:
client>smcli 123.45.67.89 -c "show storageArray defaultHostType;"
client>smcli 123.45.67.89 -c "show storageArray hostTypeTable;"
The following example shows how to define a specific default host type:
client>smcli 123.45.67.89 -c "set storageArray defaultHostType=11;"
The value 11 is the host type index value from the host type table.

Setting Modification Priority

Modification priority defines how much processing time is allocated for virtual disk modification operations. Time allocated for virtual disk modification operations affects system performance. Increases in virtual disk modification priority can reduce read/write performance. Operations affected by modification priority include:
• Copyback
• Reconstruction
• Initialization
• Changing segment size
• Defragmentation of a disk group
• Adding free capacity to a disk group
• Changing the RAID level of a disk group
The lowest priority rate favors system performance, but the modification operation takes longer. The highest priority rate favors the modification operation, but the system performance might be degraded.
The set virtualDisk command enables you to define the modification priority for a virtual disk. The following syntax is the general form of the command:
set (allVirtualDisks | virtualDisk [virtualDiskName] | virtualDisks [virtualDiskName1 ... virtualDiskNamen] | virtualDisk < accessVirtualDisk) modificationPriority=(highest | high | medium | low | lowest)
The following example shows how to use this command to set the modification priority for virtual disks named Engineering 1 and Engineering 2:
client>smcli 123.45.67.89 -c "set virtualDisks [\"Engineering_1\" \"Engineering_2\"] modificationPriority=lowest;"
The modification rate is set to lowest so that system performance is not significantly reduced by modification operations.
wwid> |
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Assigning Global Hot Spares

Hot spare physical disks can replace any failed physical disk in the storage array. The hot spare must be the same type of physical disk as the physical disk that failed and must have capacity greater than or equal to any physical disk that can fail. If a hot spare is smaller than a failed physical disk, the hot spare cannot be used to rebuild the data from the failed physical disk. Hot spares are available only for RAID levels 1 or 5.
You can assign or unassign global hot spares by using the set physicalDisk command. To use this command, you must perform these steps:
1. Identify the location of the physical disks by enclosure ID and slot ID.
2. Set the hotSpare parameter to TRUE to enable the hot spare or FALSE to disable an existing hot
spare.
The following syntax is the general form of the command:
set (physicalDisk [enclosureID,slotID] | physicalDisks [enclosureID0,slotID0 ... enclosureIDn,slotIDn] hotSpare=(TRUE | FALSE)
The following example shows how to use this command to set hot spare physical disks:
client>smcli 123.45.67.89 -c "set physicalDisks [0,2 0,3] hotSpare=TRUE;"
Enter the enclosure ID and slot ID of each physical disk that you want to use. You must put brackets ([ ]) around the list. Separate the enclosure ID and slot ID of a physical disk by a comma. Separate each enclosure ID and slot ID pair by a space.

Selecting The Event Levels For Alert Notifications

The MD storage management software has four event levels: Critical, Informational, Warning, and Debug. You can configure the MD storage management software to send alert notifications for all of these event levels or only for certain event levels.
A background task called the persistent monitor runs independently of the MD storage management software and monitors the occurrence of events on all of the managed storage arrays. The persistent monitor is installed automatically with the MD storage management software. When an event occurs, alert notifications in the form of emails and SNMP trap messages are sent to the destination addresses that are specified in the Configure Alerts dialog. For more information about how to specify the destination addresses, refer to the Configuring the Email and SNMP Alert Notification Settings online help topic in the Enterprise Management Window (EMW).
When the persistent monitor starts for the first time, a properties file is created in the directory where the MD storage management software files are located. The properties file can be configured to enable or disable local logging in the Windows and UNIX operating systems. By default, local logging is enabled in the properties file.
When local logging is enabled in the Windows operating system, the persistent monitor logs the event information in the Windows Event Log file. When local logging is enabled in the UNIX operating system, the persistent monitor logs the event information in the syslog file. The properties file can also be configured to enable or disable remote syslog notification. You must restart the persistent monitor service after configuring the properties file for the changes to take effect.
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You can configure the MD storage management software to notify only the event levels that you specify. For example, you can configure alert notifications only for Critical and Warning events.
1. Open the Configure Alerts dialog by performing one of these actions:
a. Select a storage array in the Devices tab in the EMW. b. Select Edit → Configure Alerts.
The Configure Alerts dialog is displayed. Go to step 3.
c. Select Configure Alerts in the Setup tab in the EMW. Go to step 2.
2. Select the All storage arrays radio button, and click OK.
The Configure Alerts dialog is displayed.
3. Select the Filtering tab.
4. Select the check boxes next to the event levels for which the MD storage management software
must send alert notifications.
NOTE: The configuration to send alert notifications for only certain event levels applies to all of the managed storage arrays in the MD storage management software.
5. Click OK.

Configuring Alert Notifications

You can use the Configure Alerts dialog box to set up an email alert notification in the event of an error on the network. Alert emails are sent to the specified global mail server and sender email addresses in the event of an error on the selected hosts of storage arrays. You can choose to be alerted to all problems or individual problems.
1. Open the Configure Alerts dialog box by performing one of these actions:
a. Select a storage array in the Devices tab, and then select Edit → Configure Alerts.
The Configure Alerts dialog box appears. Go to step 4.
b. On the Setup tab, select Edit → Configure Alerts. Go to step 2.
2. Select one of the following radio buttons to specify an alert level:
a. All storage arrays – To send an alert email about events on all storage arrays. Click OK.
The Configure Alerts dialog box appears. Go to step 4.
b. An individual storage array – To send an alert email about events that occur on only a specified
storage array. Click OK. The Select Storage Array dialog box appears. Go to step 3.
3. Select the storage array for which you want to receive email alerts and click OK.
The Configure Alerts dialog box appears.
NOTE: If you do not know which storage array to select, click Blink to turn on the indicator lights of the storage array.
4. Fill in the information for the selected tab and click OK.
The dialog box closes, and the Enterprise Management Window appears. An email alert is sent to the specified email address when an error occurs on the storage arrays or hosts that you selected.
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5

Using The Snapshot Feature

The following types of virtual disk snapshot premium features are supported on the MD storage array:
• Snapshot Virtual Disks using multiple point-in-time (PiT) groups
• Snapshot Virtual Disks (Legacy) using a separate repository for each snapshot
NOTE: This section describes the Snapshot Virtual Disk using PiT groups. If you are using the Snapshot Virtual Disk (Legacy) premium feature, see Using The Snapshot (Legacy) Feature.
A snapshot image is a logical image of the content of an associated base virtual disk created at a specific point-in-time, often known as a restore point. This type of image is not directly readable or writable to a host since the snapshot image is used to save data from the base virtual disk only. To allow the host to access a copy of the data in a snapshot image, you must create a snapshot virtual disk. This snapshot virtual disk contains its own repository, which is used to save subsequent modifications made by the host application to the base virtual disk without affecting the referenced snapshot image.

Before Using Snapshot CLI Commands

There are two types of virtual disk snapshot premium features supported on your storage array. Depending on your RAID controller firmware version, you may be using the legacy version of the Snapshot feature. For more information, see Using The Snapshot (Legacy) Feature.
NOTE: Ensure that you know which type of snapshot premium feature you have activated on your storage array.
For information on the differences between the two snapshot features, see the Administrator's Guide.

Snapshot Images And Groups

A snapshot image is a logical image of the content of an associated base virtual disk created at a specific point-in-time, also called a restore point. This type of image is not directly readable or writable to a host since the snapshot image is used to save data from the base virtual disk only. To allow the host to access a copy of the data in a snapshot image, you must create a snapshot virtual disk. This snapshot virtual disk contains its own repository, which is used to save subsequent modifications made by the host application to the base virtual disk without affecting the referenced snapshot image.
A snapshot image differs from a snapshot (legacy) in the following ways:
• A snapshot image uses one repository for all snapshot images associated with a base virtual disk, improving performance when there are updates to the base virtual disk.
• A snapshot image only exists within a snapshot group. To make the snapshot image read/write accessible by hosts, you must create a snapshot virtual disk.
For more information on the Snapshot feature, see the Administrator's Guide.
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Only the following can be included in a snapshot image:
• Standard virtual disks
• Thin provisioned virtual disks
• Consistency groups

Snapshot Groups And Snapshot Consistency Groups

The Snapshot Virtual Disk premium feature supports two types of snapshot groups:
• Snapshot groups
• Consistency groups

Snapshot Groups

The purpose of a snapshot group is to create a sequence of snapshot images on a given base virtual disk without impacting performance. You can set up a schedule for a snapshot group to automatically create a snapshot image at a specific time in the future or on a regular basis.
The following rules apply when creating a snapshot group:
• Snapshot groups can be created with or without snapshot images.
• Each snapshot image is a member of only one snapshot group.
• Standard virtual disks and thin virtual disks are the only types of virtual disks that can contain a snapshot group. Snapshot virtual disks cannot contain snapshot groups.
• The base virtual disk of a snapshot group can reside on either a disk group or a disk pool.
• Snapshot virtual disks and snapshot groups cannot exist on the same base virtual disk.
• A snapshot group uses a repository to save all data for the snapshot images contained in the group. A snapshot image operation uses less disk space than a full physical copy because the data stored in the repository is only the data that has changed since the latest snapshot image.
• A snapshot group is initially created with one repository virtual disk. The repository contains a small amount of data, which increases over time with subsequent data updates. You can increase the size of the repository by either increasing the capacity of the repository or adding virtual disks to the repository.

Snapshot Consistency Groups

To perform the same snapshot image operations on multiple virtual disks, you can create a consistency group containing the virtual disks. Any operation performed on the consistency group is performed simultaneously on all of the virtual disks in that group, which creates consistent copies of data between each virtual disk. Consistency groups are commonly used to create, schedule or rollback virtual disks.
Each virtual disk belonging to a consistency group is referred to as a member virtual disk. When you add a virtual disk to a consistency group, the system automatically creates a new snapshot group that corresponds to this member virtual disk. You can set up a schedule for a consistency group to automatically create a snapshot image of each member virtual disk at a specific time and/or on a regular basis.
This synchronized snapshot of all the virtual disks is especially suitable for applications that span multiple virtual disks, such as a database application containing log files on one virtual disk and the database itself on another.
The following rules apply when creating a consistency group:
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• Consistency groups can be created initially with or without member virtual disks.
• Snapshot images can be created for a consistency group to enable consistent snapshot images between all member virtual disks.
• Consistency groups can be rolled back.
• A virtual disk can belong to multiple consistency groups.
• Only standard virtual disks and thin virtual disks can be included in a consistency group.
• Snapshots created using the Snapshot Virtual Disk (Legacy) premium feature cannot be included in a consistency group.
• A base virtual disk can reside on either a disk group or disk pool.

Understanding Snapshot Repositories

Repositories are system-created virtual disks used to hold write data for snapshots, snapshot groups and consistency groups. During creation of either group or write-enabled snapshot virtual disk, an associated repository is automatically created. By default, one individual repository virtual disk is created for each snapshot group or snapshot image. You can create the overall repository automatically using the default settings, or you can manually create the repository by defining specific capacity settings.
A snapshot virtual disk allows the host access to a copy of the data contained in a snapshot image. A snapshot image is not directly read or write accessible to the host and is used only to save data captured from the base virtual disk.

Snapshot Consistency Group Repositories

A snapshot consistency group is made up of simultaneous snapshots of multiple virtual disks. Each virtual disk that belongs to a consistency group is referred to as a member virtual disk. When you add a virtual disk to a consistency group, the system automatically creates a new snapshot group that corresponds to this member virtual disk. A consistency group repository is also created for each member virtual disk in a consistency group in order to save data for all snapshot images in the group.
A consistency group snapshot image comprises multiple snapshot virtual disks. Its purpose is to provide host access to a snapshot image that has been taken for each member virtual disk at the same moment in time. A consistency group snapshot image is not directly read or write accessible to hosts; it is used only to save the data captured from the base virtual disk. The consistency group snapshot virtual disk can be designated as either read-only or read-write. Read-write consistency group snapshot virtual disks require a repository for each member virtual disk in order to save any subsequent modifications made by the host application to the base virtual disk without affecting the referenced snapshot image. Each member repository is created when the consistency group snapshot virtual disk is created.

Consistency Groups And Remote Replication

Although a virtual disk can belong to multiple consistency groups, you must create separate consistency groups for snapshot images and Remote Replication.
When a base virtual disk containing a consistency group is added to Remote Replication (non-legacy, asynchronous), the repository will automatically purge the oldest snapshot image and set the auto-delete limit to the maximum allowable snapshot limit for a consistency group.
Additionally, all member virtual disks belonging to both a snapshot consistency group and a Remote Replication group must belong to the same Remote Replication group.
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Creating Snapshot Images

Guidelines before creating a snapshot image:
• If you attempt to create a snapshot image on a snapshot group and that snapshot group has reached its maximum number of snapshot images. The failBaseWrites or purgeSnapImages parameters used with the create snapGroup command allows you to choose to either fail the write attempt or automatically purge a specified number of older snapshot images.
create snapGroup userLabel="snapGroupName" sourceVirtualDisk="virtualDiskName" repositoryVirtualDisk="repos_XXXX" [repositoryFullPolicy=(failBaseWrites | purgeSnapImages) | rollbackPriority=(high | highest | medium | low | lowest)| repositoryFullLimit=percentValue | autoDeleteLimit=numberOfSnapImages]
• If you attempt to create a snapshot image and either of the two conditions below are present, the creation might fail:
– The base virtual disk that contains this snapshot image is a member of a Remote Replication
group.
– The base virtual disk is currently synchronizing. When synchronization is complete, the snapshot
image creation will complete.

Creating A Snapshot Image

Before creating a snapshot image, you must have at least one snapshot group into which you can add the snapshot image.
Create a snapshot image using the following command:
create snapImage (snapGroup="snapGroupName" | snapGroups=("snapGroupName1"... "snapGroupName2 ..."))
where, snapGroupName or snapGroupNames is the name of the snapshot group (or groups) that you specify to hold the snapshot image.
NOTE: Ensure that you have either existing repositories, enough free capacity nodes, or available unconfigured capacity for the storage array on which you are creating the snapshot group repository.

Deleting A Snapshot Image

Use the delete snapshot image command to delete the oldest snapshot image from a snapshot group or consistency group.
After a snapshot image is deleted from a snapshot group:
• The snapshot image is deleted from the storage array.
• The repository’s reserve space is released for reuse within the snapshot group.
• All snapshot virtual disks associated with deleted snapshot image are disabled.
Use the following command to delete a snapshot image from a consistency group:
delete snapImage (snapGroup="snapGroupName" | snapGroups=("snapGroupName1"... "snapGroupNamen")) (deleteCount=numberOfSnapImages |
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retainCount=numberOfSnapImages | ignoreSnapVirtualDisk=(TRUE | FALSE) | snapImageID=OLDEST)

Creating A Consistency Group Snapshot Virtual Disk

Creating a snapshot virtual disk of a consistency group creates a viewable virtual disk of specific images in the consistency group. A consistency group snapshot virtual disk can be made up of a single base virtual disk or multiple base virtual disks from the consistency group.
This command also allows you to set the following attributes for the snapshot virtual disk:
• read-only
• repository full value
• automatic repository selection
Unique command syntax and naming rules apply. The name of a snapshot image has two parts separated by a colon (:):
• identifier of the snapshot group
• identifier of the snapshot image
If you do not specify the repositoryVirtualDiskType or readOnly parameters, the repositories for the consistency group snapshot virtual disk will be selected automatically. If the disk group or disk pool where the base virtual disk resides does not have enough space, the command will fail.
Create a read/write consistency group snapshot virtual disk on a snapshot consistency group named snapCG1 with these three members cgm1, cgm2, and cgm3. The repository virtual disks already exist and are selected in this command.
create cgSnapVirtualDisk userLabel="cgSnapVirtualDisk1" cgSnapImageID="snapCG1:oldest" members=(cgm1:repos_0010 cgm2:repos_0011 cgm3:repos_0007);
Note the colon (:) in the name of the snapshot image to be included in the consistency group snapshot virtual disk. The colon is a delimiter that separates the name of the snapshot virtual disk from a particular snapshot image that you might want to use. Any of the following three options can be used following the colon:
• An integer value that is the actual sequence number of the snapshot image.
• NEWEST specifies the latest consistency group snapshot image.
• OLDEST specifies the earliest snapshot image created.
The use of the colon following the names of the members of the snapshot consistency group define the mapping between the member and a repository virtual disk. For example:
cgm1:repos_10, member cgm1 maps to repository virtual disk repos_0010
Create a read-only consistency group snapshot virtual disk on a snapshot consistency group named snapCG1 with members cgm1, cgm2, and cgm3 using the following command:
create cgSnapVirtualDisk userLabel="cgSnapVirtualDisk3" cgSnapImageID="snapCG1:oldest" readOnly;
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Create a consistency group snapshot virtual disk that has a repository full limit set to 60 percent on a snapshot consistency group named snapCG1 with these three members cgm1, cgm2, and cgm3, with the following command:
create cgSnapVirtualDisk userLabel="cgSnapVirtualDisk3" cgSnapImageID="snapCG1:oldest" repositoryFullLimit=60;
Create a read/write consistency group snapshot virtual disk with automatic repository selection on a snapshot consistency group named snapCG1 with members cgm1, cgm2, and cgm3, with the following command:
create cgSnapVirtualDisk userLabel="cgSnapVirtualDisk4" cgSnapImageID="snapCG1:oldest";

Creating A Consistency Group Snapshot Image

To create a new snapshot image for each base virtual disk in snapshot consistency group, use the create cgSnapImage command. The command will suspend all pending I/O operations to each base virtual disk that is a member of the consistency group before creating the snapshot images. If the snapshot image cannot be completed successfully for all of the consistency group members, this command fails and new snapshot images are not created.
Since all members of a snapshot consistency group normally contain the same number of snapshot images, adding a new member to a snapshot consistency group with this command create a new member lacking previously created snapshot images. This is not an indication of an error condition.
To create a consistency group snapshot image:
create cgSnapImage consistencyGroup="consistencyGroupName"
where, consistencyGroup is the name of the consistency group for which you are creating snapshot images.

Deleting A Snapshot Virtual Disk Or A Consistency Group Snapshot Virtual Disk

You can use the following command to delete a snapshot virtual disk or a consistency group snapshot virtual disk. Optionally, you can also delete the repository members.
delete cgSnapVirtualDisk ["snapVirtualDiskName"] [deleteRepositoryMembers=(TRUE | FALSE)];
where, snapVirtualDiskName is the snapshot you want to delete. The deleteRepositoryMembers=TRUE parameter will preserve the member virtual disks (default). Setting the parameter to FALSE will delete the member virtual disks.

Deleting A Consistency Group Snapshot Image

You can delete the snapshot images in a consistency group. However, when you delete a consistency group snapshot image that is associated with a consistency group snapshot virtual disk, the corresponding snapshot virtual disk member in the consistency group snapshot virtual disk is transitioned to a Stopped state. Being in this state means that the snapshot virtual disk member no longer has a relationship to the snapshot group of the deleted snapshot image. A snapshot virtual disk member in a Stopped state maintains its relationship to its consistency group snapshot virtual disk.
When a snapshot image(s) is deleted from a consistency group:
• The snapshot is deleted from the storage array.
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• The repository’s reserve space for reuse within the consistency group is released.
• Any member virtual disk associated with the deleted snapshot image(s) is moved to a Stopped state.
• The member snapshot virtual disks associated with the deleted snapshot image(s) is deleted.
To delete two snapshot images named all_data_1 from a consistency group, use the following command:
delete cgSnapImage consistencyGroup="all_data_1"
To succeed, all snapshot images must be deleted or the command will fail and no snapshots will be deleted.

Scheduling Snapshot Images

Using the enableSchedule and schedule parameters with virtual disk and consistency group commands, you can schedule regular snapshot images to recover files or schedule regular backups. The schedule can be set when you initially create a snapshot group or consistency group, or you can add it later to an existing snapshot group or consistency group.
You can create a schedule that runs daily or weekly in which you select specific days of the week (Sunday through Saturday).
An example of the set snapGroup command using the schedule parameters:
set snapGroup ["snapGroupName"] enableSchedule=(TRUE | FALSE) schedule=(immediate | snapshotSchedule)
Valid schedule values for the schedule parameter are immediate, startDate, scheduleDay, startTime, scheduleInterval, endDate, noEndDate, timesPerDay and timeZone.
For more information, see:
• Set Snapshot Group Attributes
• Create Snapshot Group
• Create Consistency Group

Starting, Stopping And Resuming A Snapshot Rollback

The command line interface allows you to:
• start a rollback operation from multiple snapshot images concurrently
• stop a rollback operation
• resume a rollback operation
When rolling back, the host will have immediate access to the new-rolled-back base virtual disk, but the existing base virtual disk will not allow the host read-write access once the rollback is initiated.
NOTE: Create a snapshot of the base virtual disk just prior to initiating the rollback to preserve the pre-rollback base virtual disk for recovery purposes.
When you start a rollback operation for a set of snapshot images, the content of the base virtual disk changes immediately to match the point-in-time content of the selected snapshot image virtual disk. The base virtual disk immediately becomes available for read/write requests after the rollback operation has successfully completed.
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To start a rollback for a snapshot group named snapGroup1:
start snapImage ["snapGroup1"] rollback
You can specify a snapshot image rollback for a specific snapshot image in a snapshot group named 12345:
stop snapImage ["snapGroup1:12345"] rollback;
To stop a rollback operation for the most recent snapshot image in a snapshot group that has the name snapGroup1:
stop snapImage ["snapGroup1:newest"] rollback;
The repository virtual disk associated with the snapshot image continues to track any new changes between the base virtual disk and the snapshot image virtual disk that occur after the rollback operation is completed.
To resume a rollback operation for the same snapshot image and snapshot group:
resume snapImage ["snapgroup1:12345"] rollback;

Creating A Snapshot Group

A snapshot group is a sequence of point-in-time images of a single associated base virtual disk. A snapshot group uses a repository to save data for all snapshot images contained in the group. The repository is created at the same time the snapshot group is created.
Guidelines when creating a snapshot group:
• When a base virtual disk that contains a snapshot group is added to an asynchronous remote replication group, the system automatically changes the repository full policy to automatically purge the oldest snapshot image and sets the auto-delete limit to the maximum allowable snapshot limit for a snapshot group.
• If the base virtual disk resides on a standard disk group, the repository members for any associated snapshot group can reside on either a standard disk group or a disk pool. If a base virtual disk resides on a disk pool, all repository members for any associated snapshot group must reside on the same disk pool as the base virtual disk.
• You cannot create a snapshot group on a failed virtual disk.
• If you attempt to create a snapshot image, that snapshot image creation operation might remain in a Pending state because of the following conditions:
– The base virtual disk that contains this snapshot image is a member of an asynchronous remote
replication group.
– The base virtual disk is currently in a synchronizing operation. The snapshot image creation
completes as soon as the synchronization operation is complete.
To create a snapshot group:
create snapGroup userLabel="snapGroupName" sourceVirtualDisk="virtualDiskName" (repositoryVirtualDisk="repos_xxxx" | repositoryVirtualDisk=( [capacity=capacityValue]) repositoryVirtualDisk=(diskPoolName [capacity=capacityValue])) [repositoryFullPolicy=(failBaseWrites | purgeSnapImages) | rollbackPriority=(highest | high | medium | low | lowest) | repositoryFullLimit=percentValue | autoDeleteLimit=numberOfSnapImages | enableSchedule=(TRUE | FALSE) schedule=(immediate | snapshotSchedule)]
diskGroupName
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Deleting A Snapshot Group

CAUTION: All of the data in the snapshot group is lost as soon as you run this command.
This command deletes an entire snapshot group and, if specified, the associated repository virtual disks.
delete snapGroup ["snapGroupName"] deleteRepositoryMembers=TRUE;
In the example, the repository virtual disks were preserved . By default, all member virtual disks in the repository virtual disk are retained as unused, unmapped standard virtual disks. Setting the deleteRepositoryMembers parameter to FALSE will delete the repository disks.

Reviving A Snapshot Group

If a snapshot group is not in a Failed state, it can be forced into an Optimal state. Running this command on a Failed snapshot will return an error message and the command will not complete.
revive snapGroup ["snapGroupName"];
where snapGroupName is the name of the snapshot group you want to force into an Optimal state.

Creating A Consistency Group

A consistency group contains simultaneous snapshots of multiple virtual disks to ensure consistent copies of a group of virtual disks. When you add a virtual disk to a consistency group, the system automatically creates a new snapshot group that corresponds to this member virtual disk.
The following command creates a new, empty consistency group. You must add the snapshot groups using the set consistencyGroup addCGMember command.
create consistencyGroup userLabel="consistencyGroupName" [repositoryFullPolicy=(failBaseWrites | purgeSnapImages) | repositoryFullLimit=percentValue | autoDeleteLimit=numberOfSnapImages | enableSchedule=(TRUE | FALSE) | schedule (immediate | snapSchedule) | rollbackPriority=(lowest | low | medium | high | highest)]
where userLabel is the name of the new consistency group you want to create. repositoryFullPolicy controls how you want snapshot processing to continue if the snapshot
repository virtual disks are full. You can choose to fail writes to the base virtual disk ( delete the snapshot images (purgeSnapImages). The default action is to delete the snapshot images.
The repositoryFullLimit parameter controls the percentage of repository capacity at which you receive a warning that the snapshot repository virtual disk is nearing full. Use integer values. autoDeleteLimit configures the automatic deletion thresholds of snapshot images to keep the total number of snapshot images in the snapshot group at or below a designated level. When this option is enabled, then any time a new snapshot image is created in the snapshot group, the system automatically deletes the oldest snapshot image in the group to comply with the limit value. This action frees repository capacity so it can be used to satisfy ongoing copy-on-write requirements for the remaining snapshot images.
For other values, see Create Consistency Group.
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Deleting A Consistency Group

This command deletes a snapshot consistency group. You can either delete both the consistency group and the repository virtual disks contained by the consistency group, or you can delete only the consistency group and leave the repository virtual disks contained in the consistency group intact.
delete consistencyGroup [consistencyGroupName [deleteRepositoryMembers=(TRUE | FALSE)]]
To delete the consistency group and the repository virtual disks, set the deleteRepositoryMembers parameter to TRUE. To retain the repository virtual disks, set this parameter to FALSE. The default setting is FALSE.
Once completed, this command:
• Deletes all existing snapshot images and snapshot virtual disks from the consistency group.
• Deletes all the associated snapshot images and snapshot virtual disks for each member virtual disk in the consistency group.
• Deletes all associated repositories for each member virtual disk in the consistency group (if selected).

Setting Consistency Group Attributes

To change or set the properties for a snapshot consistency group, use the set consistencyGroup command:
set consistencyGroup ["consistencyGroupName"] [userLabel="consistencyGroupName" | repositoryFullPolicy=(failBaseWrites | purgeSnapImages)| repositoryFullLimit=percentValue| autoDeleteLimit= rollbackPriority=(lowest | low | medium | high | highest)]
numberOfSnapImages|
The repositoryFullPolicy parameter determines how you want snapshot processing to continue if the snapshot repository virtual disks are full. You can choose to fail writes to the base virtual disk (failBaseWrites) or delete (purgeSnapImages) the snapshot images. The default action is to delete the images.
The repositoryFullLimit controls the percentage of repository capacity at which you receive a warning that the snapshot repository virtual disk is nearing full. Use integer values. autoDeleteLimit configures the automatic deletion thresholds of snapshot images to keep the total number of snapshot images in the snapshot group at or below a designated level. When this option is enabled, then any time a new snapshot image is created in the snapshot group, the system automatically deletes the oldest snapshot image in the group to comply with the limit value. This action frees repository capacity so it can be used to satisfy ongoing copy-on-write requirements for the remaining snapshot images.
The rollBackPriority parameter sets priority level for a consistency group rollback in an operational storage array.
For example, use this command on a consistency group named CGGroup_1:
set consistencyGroup ["CGGroup_1"] autoDeleteLimit=6 rollbackPriority=low;
Valid values are highest, high, medium, low, or lowest. The rollback priority defines the amount of system resources that should be allocated to the rollback operation at the expense of system performance. A value of Lower values indicate that the rollback operation should be performed with minimal impact to host I/O.
high indicates that the rollback operation is prioritized over all other host I/O.
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autoDeleteLimit allows you to configure each snapshot group to perform automatic deletion of its snapshot images to keep the total number of snapshot images in the snapshot group at or below a maximum number of images. When the number of snapshot images in the snapshot group is at the maximum limit, the autoDeleteLimit parameter automatically deletes snapshot images whenever a new snapshot image is created in the snapshot group. The oldest snapshot images in the snapshot group until the maximum number of images defined with the parameter is met. Deleting snapshot images frees repository capacity so it can be used to satisfy ongoing copy-on-write requirements for the remaining snapshot images.

Adding A Member Virtual Disk To A Consistency Group

To add a new base virtual disk to an existing consistency group, specify an existing repository virtual disk for the new consistency group member or create a new repository virtual disk. When creating a new repository virtual disk, identify an existing disk group or disk pool in which to create the repository virtual disk.
To add a new base virtual disk to a consistency group with an existing virtual disk:
set consistencyGroup ["consistencyGroupName"] addCGMemberVirtualDisk="baseVirtualDiskName" repositoryVirtualDisk="repos_XXXX"
To add a new base virtual disk to a consistency group and create a new repository virtual disk using a disk group:
set consistencyGroup ["consistencyGroupName"] addCGMemberVirtualDisk="baseVirtualDiskName" repositoryVirtualDisk=("diskGroupName" capacity=capacityValue(KB|MB|GB|TB| bytes))
To add a new base virtual disk to a consistency group and create a new repository virtual disk using a disk pool:
set consistencyGroup ["consistencyGroupName"] addCGMemberVirtualDisk="baseVirtualDiskName" repositoryVirtualDisk=("diskPoolName" capacity=capacityValue(KB|MB|GB|TB|bytes))
Restrictions
• The Snapshot premium feature must be enabled on the storage array.
• To add a new member virtual disk, the consistency group must fewer than the maximum number of virtual disks allowed in your configuration.
• If the base virtual disk resides on a standard disk group, the repository members for any associated consistency group can reside on either a standard disk group or a disk pool. If a base virtual disk resides on a disk pool, the repository members for any associated consistency group must reside on the same disk pool as the base virtual disk.
• You cannot add a virtual disk to a consistency group that is in a Failed state.

Removing A Member Virtual Disk From A Consistency Group

When removing a member virtual disk from an existing snapshot consistency group, you can also delete the repository virtual disk members from the consistency group, if desired.
The remove command syntax is shown below:
set consistencyGroup ["consistencyGroupName"] removeCGMemberVirtualDisk="memberVirtualDiskName" [deleteRepositoryMembers=(TRUE | FALSE)]
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The removeCGMemberVirtualDisk parameter is the name of the member virtual disk that you want to remove; deleteRepositoryMembers determines whether the command removes all the repository members from the consistency group.
To remove a virtual disk names payroll-backup from a consistency group named CGGroup_1, but preserve the repository virtual disks:
set consistencyGroup ["CGGroup_1"] removeCGMemberVirtualDisk="payroll_backup" deleteRepositoryMembers=FALSE;
To remove CGGroup_1, as well as all repository virtual disks:
set consistencyGroup ["CGGroup_1"] removeCGMemberVirtualDisk=" payroll_backup" deleteRepositoryMembers=TRUE;
Or omit the deleteRepositoryMembers parameter, which invokes the default value of preserving repository virtual disks:
set consistencyGroup ["CGGroup_1"] removeCGMemberVirtualDisk=" payroll_backup";

Changing The Pre-read Consistency Check Setting Of An Overall Repository Virtual Disk

Use the Pre-Read Consistency Check option to define a storage array's capability to pre-read an overall repository virtual disk consistency information and determine whether the data of that overall repository virtual disk is consistent. An overall repository virtual disk that has this feature enabled returns read errors if the data is determined to be inconsistent by the RAID controller module firmware.
You can enable this option for overall repository virtual disks that contain consistency information. RAID Level 1, RAID Level 5, and RAID Level 6 maintain redundancy information.
You can change the Pre-Read Consistency Check for an overall repository for the following storage objects:
• Snapshot group
• Snapshot virtual disk
• Consistency group member virtual disk
• Replicated Pair
This command defines the properties for a virtual disk. You can use most parameters to define properties for one or more virtual disks. You can also use some parameters to define properties for only one virtual disk. The syntax definitions are separated to show which parameters apply to several virtual disks and which apply to only one virtual disk.
NOTE: In configurations where disk groups consist of more than 32 virtual disks, the operation can result in host I/O errors or internal RAID controller module reboots due to the expiration of the timeout period before the operation completes. If you experience host I/O errors or internal RAID controller module reboots, quiesce the host I/O and try the operation again.
Syntax Applicable To One Or More Virtual Disks
set (allVirtualDisks | virtualDisk ["virtualDiskName"] | virtualDisks ["virtualDiskName1" ... "virtualDiskNameN"] | virtualDisk <wwID>) cacheFlushModifier=cacheFlushModifierValue cacheWithoutBatteryEnabled=(TRUE | FALSE) mediaScanEnabled=(TRUE | FALSE) replicationCacheEnabled=(TRUE | FALSE) modificationPriority=(highest | high | medium | low | lowest) owner=(0 | 1)
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preReadConsistencyCheck=(TRUE | FALSE) readCacheEnabled=(TRUE | FALSE) writeCacheEnabled=(TRUE | FALSE) cacheReadPrefetch=(TRUE | FALSE)
Syntax Applicable To Only One Virtual Disk
set (virtualDisk ["virtualDiskName"] | virtualDisk <wwID>) addCapacity=virtualDiskCapacity [addPhysicalDisks=(enclosureID1,drawerID1,slotID1 ... enclosureIDn,drawerIDn,slotIDn)] consistencyCheckEnabled=(TRUE | FALSE) segmentSize=segmentSizeValue userLabel=virtualDiskName preReadConsistencyCheck=(TRUE | FALSE)
preReadConsistencyCheck
The setting to turn on or turn off preread consistency checking. Turning on preread consistency checking verifies the consistency of RAID redundancy data for the stripes containing the read data. Preread consistency checking is performed on read operations only. To turn on preread consistency checking, set this parameter to TRUE. To turn off preread consistency checking, set this parameter to FALSE.
NOTE: Do not use this parameter on non-redundant virtual disks, such as RAID 0 virtual disks.
Guidelines while using the Pre-Read Consistency Check option:
• Changing the Pre-Read Consistency Check setting modifies the setting only for the overall repository that you selected.
• The Pre-Read Consistency Check setting is applied to all individual repository virtual disks contained within the overall repository.
• If an overall repository virtual disk that is configured with pre-read is migrated to a RAID level that does not maintain consistency information, the metadata of the overall repository virtual disk continues to show that pre-read is enabled. However, reads to that overall repository virtual disk ignores consistency pre-read. If the virtual disk is subsequently migrated back to a RAID level that supports consistency, the option becomes available again.
NOTE: Enabling the option on overall repository virtual disks without consistency does not affect the virtual disk. However, the attribute is retained for that overall repository virtual disk if it is ever changed to one with consistency information.

Setting Snapshot Virtual Disk Repository Virtual Disk Capacity

To increase or decreases the capacity of a snapshot virtual disk repository virtual disk, use the set snapVirtualDisk command.
A snapshot repository virtual disk is an expandable virtual disk that is structured as a concatenated collection of up to 16 standard virtual disk entities. Initially, an expandable repository virtual disk has only a single element. The capacity of the expandable repository virtual disk is exactly that of the single element. You can increase the capacity of an expandable repository virtual disk by attaching additional standard virtual disks to it. The composite expandable repository virtual disk capacity then becomes the sum of the capacities of all of the concatenated standard virtual disks.
A snapshot group repository virtual disk must satisfy a minimum capacity requirement that is the sum of the following:
• 32 MB to support fixed overhead for the snapshot group and for copy-on-write processing.
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• Capacity for rollback processing, which is 1/5000th of the capacity of the base virtual disk.
If you are creating a new repository virtual disk when you run this command, you must enter the name of a disk group or disk pool from which you want the repository virtual disk. Optionally, you can also define the capacity of the repository virtual disk. The following capacity values are supported:
• A percentage ( integer value) representing an amount of the base virtual disk capacity.
• A decimal fraction representing a percentage of the base virtual disk capacity.
• A specific size for the repository virtual disk, in units of bytes, KB, MB, GB, or TB.
To increase capacity for a snapshot virtual disk, use the increaseRepository Capacity and
capacity parameter as shown below:
set snapVirtualDisk[“snapVirtualDiskName”] increaseRepositoryCapacity repositoryVirtualDisks=("repos_xxxx" | repositoryVirtualDisks=(diskGroupName [capacity=capacityValue]) repositoryVirtualDisks=(diskPoolName [capacity=capacityValue]))
To decrease capacity, replace increaseRepositoryCapacity with decreaseRepository:
set snapVirtualDisk ["snapVirtualDiskName"] decreaseRepositoryCapacity count=numberOfVirtualDisks

Setting Snapshot Group Repository Virtual Disk Capacity

To increase or decrease capacity of a snapshot group repository virtual disk, use the same basic command syntax as shown previously for the virtual disk repository, except use the set snapGroup command and supply the snapshot group name:
set snapGroup ["snapGroupName"] increaseRepositoryCapacity (repositoryVirtualDisks="repos_xxxx" | repositoryVirtualDisks=(( [capacity=capacityValue])) | repositoryVirtualDisks=((diskPoolName [capacity=capacityValue])))
diskGroupName
For more information about expanding storage objects, see the Administrator's Guide.

Reviving Disk Groups, Physical Disks, Snapshot Groups, And Snapshot Virtual Disks

The revive command forces failed physical disks, disk groups, snapshot groups and snapshot virtual disks into an Optimal state. However, this command should only be performed by qualified storage administrators.
CAUTION: Possible loss of data access—Correct use of this command depends on the data configuration on the physical disks in the disk group. Do not attempt to revive a physical disk or disk group unless you are explicitly directed by your Technical Support representative.
To revive a physical disk:
revive physicalDisk [enclosureID,drawerID,slotID]
For MD-series dense storage arrays, all three location attributes (enclosureID, drawerID and slotID) are required. For non-dense storage arrays, only enclosureID and slotID are required. Valid enclosureID values are 0 to 99, drawerID values are 0 to 4 and slotID values are 0 to 31.
To revive disk group:
revive diskGroup [diskGroupName]
To revive a snapshot virtual disk, the snapshot virtual disk must be a:
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• standalone snapshot virtual disk
• snapshot virtual disk that is a member of a consistency group
If the snapshot virtual disk is not in a Failed state, the firmware displays an error message and does not run this command.
revive snapVirtualDisk ["snapVirtualDiskName"]
NOTE: This command for a snapshot virtual disk used in online virtual disk copy.
To revive a snapshot group:
revive snapGroup ["snapGroupName"]
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6

Using The Snapshot (Legacy) Feature

The following types of virtual disk snapshot premium features are supported on the MD storage array:
• Snapshot Virtual Disks using multiple point-in-time (PiT) groups
• Snapshot Virtual Disks (Legacy) using a separate repository for each snapshot
NOTE: This section describes the Snapshot Virtual Disk (legacy) premium feature. If you are using the Snapshot Virtual Disk using PiT groups, see Using The Snapshot Feature.
This chapter describes how the Snapshot (legacy) feature works, lists the snapshot script commands, and explains how to use the commands to create snapshot virtual disks. Additional information about the Snapshot (legacy) feature and related definitions is available in the online help, the Deployment Guide, the MD Storage Manager online help, and the Owner’s Manual.
The Snapshot (legacy) feature creates a snapshot virtual disk that you can use as a backup of your data. A snapshot virtual disk is a logical point-in-time image of a standard virtual disk. Because it is not a physical copy, a snapshot virtual disk is created more quickly than a physical copy and requires less physical disk space. Typically, you create a snapshot virtual disk so that an application, such as a backup application, can access the snapshot virtual disk. The application reads the data while the source virtual disk remains online and user accessible. You can also create several snapshot virtual disks of a source virtual disk and write data to the snapshot virtual disks to perform testing and analysis.
NOTE: If you ordered Premium Features for the Snapshot Virtual Disks, you would have received a Premium Features Activation card shipped in the same box as your Dell PowerVault MD storage array. Follow the directions on the card to obtain a key file and to enable the feature. For more information, see Premium Feature — Snapshot Virtual Disks in the Owner’s Manual.
Snapshot virtual disks allow you to perform the following tasks:
• Create a complete image of the data on a source virtual disk at a particular point in time.
• Use only a small amount of disk space.
• Provide quick, frequent, nondisruptive backups; or test new versions of a database system without affecting actual data.
• Provide for snapshot virtual disks to be read, written, and copied.
• Use the same availability characteristics of the source virtual disk (such as redundant array of independent disks (RAID) protection and redundant path failover).
• Map the snapshot virtual disk and make it accessible to any host on a storage area network. You can make snapshot data available to secondary hosts for read and write access by mapping the snapshot to the hosts.
• Create up to four snapshots per virtual disk.
NOTE: The maximum number of snapshot virtual disks is one-half of the total number of virtual disks supported by the RAID controller module.
• Increase the capacity of a snapshot virtual disk.
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The following table lists the components that comprise a snapshot virtual disk and briefly describes what they do.
Table 9. Snapshot Virtual Disk Components
Component Description
Source virtual disk Standard virtual disk from which the snapshot is
created
Snapshot virtual disk Point-in-time image of a standard virtual disk
Snapshot repository virtual disk Virtual disk that contains snapshot metadata and
copy-on-write data for a particular snapshot virtual disk
The following table lists the snapshot virtual disk commands and brief descriptions of what the commands do.
Table 10. Snapshot Virtual Disk Commands
Command Description
create snapshotVirtualDisk
re-create snapshot
set (snapshotVirtualDisk)
stop snapshot
Creates a snapshot virtual disk.
Starts a fresh copy-on-write operation by using an existing snapshot virtual disk.
Defines the properties for a snapshot virtual disk and enables you to rename a snapshot virtual disk.
Stops a copy-on-write operation.

Using Host Servers To Create An Initial Snapshot Virtual Disk

CAUTION: Before using the Snapshot Virtual Disks Premium Feature in a Microsoft Windows clustered configuration, you must first map the snapshot virtual disk to the cluster node that owns the source virtual disk. This ensures that the cluster nodes correctly recognize the snapshot virtual disk.
If you map the snapshot virtual disk to the node that does not own the source virtual disk before the snapshot enabling process is completed, the operating system may fail to correctly identify the snapshot virtual disk. This can result in data loss on the source virtual disk or an inaccessible snapshot.
NOTE: You can create concurrent snapshots of a source virtual disk on both the source disk group and on another disk group.
Before creating a Snapshot Virtual Disk, note the following:
• The following types of virtual disks are not valid source virtual disks: snapshot repository virtual disks, snapshot virtual disks, target virtual disks that are participating in a virtual disk copy.
• You cannot create a snapshot of a virtual disk that contains unreadable sectors.
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• You must satisfy the requirements of your host operating system for creating snapshot virtual disks. Failure to meet the requirements of your host operating system results in an inaccurate point-in-time image of the source virtual disk or the target virtual disk in a virtual disk copy.

Creating A Snapshot Virtual Disk

The create snapshotVirtualDisk command provides three methods for defining the physical disks for your snapshot repository virtual disk:
• Define each physical disk for the snapshot repository virtual disk by enclosure ID and slot ID.
• Define a disk group in which the snapshot repository virtual disk resides. Optionally define the capacity of the repository virtual disk.
• Define the number of physical disks, but not specific physical disks, for the repository virtual disk.
When using the create snapshotVirtualDisk command to create a snapshot virtual disk, the standard virtual disk name for the source virtual disk is the minimum information required. When you provide only the standard virtual disk name, the storage management software provides default values for the other required property parameters for a snapshot virtual disk.
NOTE: In some cases, depending on the host operating system and any virtual disk manager software in use, the software prevents you from mapping the same host to both a source virtual disk and its associated snapshot virtual disk.
An error message appears in the command line when the utility cannot distinguish between the following:
• Source virtual disk and snapshot virtual disk (for example, if the snapshot virtual disk has been removed)
• Standard virtual disk and virtual disk copy (for example, if the virtual disk copy has been removed)
If you are running a Linux operating system, run the hot_add utility to register the snapshot virtual disk with the host operating system.
NOTE: The hot_add utility is not available for Windows.

Enabling The Snapshot Virtual Disk Feature

The first step in creating a snapshot virtual disk is to make sure the feature is enabled on the storage array. You need a feature key to enable the feature. The command for enabling the feature key file is:
enable storageArray feature file="filename"
where, the file parameter is the complete file path and file name of a valid feature key file. Enclose the file path and file name in quotation marks (" "). Valid file names for feature key files usually end with .key extension.

Creating A Snapshot Virtual Disk With User-Assigned Physical Disks

Creating a snapshot virtual disk by assigning the physical disks allows you to choose from the available physical disks when defining your storage array configuration. When you choose the physical disks for your snapshot virtual disk, you automatically create a new disk group. You can specify which physical disks to use and the RAID level for the new disk group.
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Preparing Host Servers To Create An Initial Snapshot Virtual Disk

CAUTION: Before you create a new point-in-time image of a source virtual disk, stop any data access (I/O) activity or suspend data transfer to the source virtual disk to ensure that you capture an accurate point-in-time image of the source virtual disk. Close all applications, including Windows Internet Explorer, to make sure all I/O activity has stopped.
NOTE: Removing the drive letter of the associated virtual disk(s) in Windows or unmounting the virtual drive in Linux helps to guarantee a stable copy of the drive for the Snapshot.
Before creating a snapshot virtual disk, the server has to be in the proper state. To ensure that the host server is properly prepared to create a snapshot virtual disk, you can either use an application to carry out this task, or you can perform the following steps:
1. Stop all I/O activity to the source.
2. Using your Windows system, flush the cache to the source. At the host prompt, type SMrepassist
-f <filename-identifier>
See "SMrepassist Utility" in the Owner’s Manual for more information.
3. Remove the drive letter(s) of the source in Windows or unmount the virtual drive(s) in Linux to help
guarantee a stable copy of the drive for the Snapshot. If this is not done, the snapshot operation reports that it has completed successfully, but the snapshot data is not updated properly.
NOTE: Verify that the virtual disk has a status of Optimal or Disabled by clicking the Summary tab and then clicking the Disk Groups & Virtual Disks link.
4. Follow any additional instructions for your operating system. Failure to follow these additional
instructions can create unusable snapshot virtual disks.
NOTE: If your operating system requires additional instructions, you can find those instructions in your operating system documentation.
and press <Enter>.
If you want to use a snapshot regularly, such as for backups, use the Disable Snapshot and Re-create Snapshot options to reuse the snapshot. Disabling and re-creating snapshots preserves the existing virtual disk-to-host mappings to the snapshot virtual disk.
After your server has been prepared, see Creating The Initial Snapshot Virtual Disk.

Creating The Initial Snapshot Virtual Disk

After preparing the host server(s) as specified in the preceding procedure, use the following examples to make a virtual disk snapshot.
The following syntax is the general form of the command to create a snapshot virtual disk:
create snapshotVirtualDisk sourceVirtualDisk= "sourceVirtualDiskName" [repositoryRAIDLevel=(0 | 1 | 5) (repositoryPhysicalDisks=
enclosureID0,slotID0 ... enclosureIDn,slotIDn)
( userLabel="snapshotVirtualDiskName" warningThresholdPercent=percentValue repositoryPercentOfSource=percentValue repositoryUserLabel="repositoryName" repositoryFullPolicy=(failSourceWrites | failSnapShot)] [enclosureLossProtect=(TRUE | FALSE)]enableSchedule=(TRUE | FALSE) | schedule= (immediate | snapshotSchedule)]
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NOTE: Use one or all of the optional parameters as needed to help define your configuration. You do not need to use any optional parameters.
See step 1 through step 4 in the preceding section, Preparing Host Servers To Create An Initial Snapshot Virtual Disk. The following example shows a command in which users assign the physical disks:
client>smcli 123.45.67.89 -c "create snapshotVirtualDisk sourceVirtualDisk= \"Mars_Spirit_4\" repositoryRAIDLevel=5 repositoryPhysicalDisks=(1,1 1,2 1,3 1,4 1,5);"
The command in this example creates a new snapshot of the source virtual disk Mars_Spirit_4. The snapshot repository virtual disk consists of five physical disks that form a new disk group. The new disk group has a RAID level of 5. This command also takes a snapshot of the source virtual disk, starting the copy-on-write operation.
See step 1 through step 4 in the preceding section, Preparing Host Servers To Create An Initial Snapshot Virtual Disk. The following example is the script file version of the command:
create snapshotVirtualDisk sourceVirtualDisk= "Mars_Spirit_4" repositoryRAIDLevel=5 repositoryPhysicalDisks=(1,1 1,2 1,3 1,4 1,5);
A minimal version of this command might look like the following example:
client>smcli 123.45.67.89 -c "create snapshotVirtualDisk sourceVirtualDisk= \"Mars_Spirit_4\";"
The command in this example creates a new snapshot for the source virtual disk Mars_Spirit_4. The repository virtual disk is created in the same disk group as the source virtual disk, which means that the repository virtual disk has the same RAID level as the source virtual disk. This command starts the copy­on-write operation.
Refer to steps 1 through 4 in the preceding section, Preparing Host Servers To Create An Initial Snapshot Virtual Disk. The following example is the script file version of the command:
create snapshotVirtualDisk sourceVirtualDisk= "Mars_Spirit_4";

Creating A Snapshot Virtual Disk With Software-Assigned Physical Disks

This version of the create snapshotVirtualDisk command lets you choose an existing disk group to place the snapshot repository virtual disk. The storage management software determines which physical disks to use. You can also define how much space to assign to the repository virtual disk. Because you are using an existing disk group, the RAID level for the snapshot virtual disk defaults to the RAID level of the disk group in which you place it. You cannot define the RAID level for the snapshot virtual disk. The general syntax for this command is:
create snapshotVirtualDisk sourceVirtualDisk= "sourceVirtualDiskName" [repositoryDiskGroup=
diskGroupNumber freeCapacityArea= freeCapacityIndexNumber userLabel=
"snapshotVirtualDiskName" warningThresholdPercent=percentValue repositoryPercentOfSource=percentValue repositoryUserLabel="repositoryName" repositoryFullPolicy=(failSourceWrites | failSnapShot)] [enclosureLossProtect=(TRUE | FALSE)]
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NOTE: Use one or all of the optional parameters as needed to define your configuration. It is not necessary to use any optional parameters.
The following example is a command in which software assigns the physical disks:
client>smcli 123.45.67.89 -c "create snapshotVirtualDisk sourceVirtualDisk= \"Mars_Spirit_4\" repositoryDiskGroup=2 freeCapacityArea=2;"
The command in this example creates a new snapshot repository virtual disk in disk group 2. The source virtual disk is Mars_Spirit_4. The size of the snapshot repository is 4 GB. This command also takes a snapshot of the source virtual disk, which starts the copy-on-write operation.
Define the capacity of a snapshot repository virtual disk as any percentage of the size of the source virtual disk. A value of 20 percent is an optimum number. In the previous example, the size of the snapshot repository is set to 4 GB. The underlying assumption is that the source virtual disk size is 20 GB (0.2 x 20 GB = 4 GB).
The following example is the script file version of the command:
create snapshotVirtualDisk sourceVirtualDisk= "Mars_Spirit_4" repositoryDiskGroup=2 freeCapacityArea=2;

Creating A Snapshot Virtual Disk By Specifying A Number Of Physical Disks

With this version of the create snapshotVirtualDisk command, you must specify the number of physical disks and the RAID level for the snapshot repository virtual disk. This version of the create snapshotVirtualDisk command creates a new disk group. You must have physical disks in the storage array that are not assigned to a disk group for this command to work:
create snapshotVirtualDisk sourceVirtualDisk= "sourceVirtualDiskName" [repositoryRAIDLevel=(0 | 1 | 5 | 6) repositoryPhysicalDiskCount= numberOfPhysicalDisks physicalDiskType=(SAS) userLabel="snapshotVirtualDiskName" warningThresholdPercent=percentValue repositoryPercentOfSource=percentValue repositoryUserLabel="repositoryName" repositoryFullPolicy=(failSourceWrites | failSnapShot)] [enclosureLossProtect=(TRUE | FALSE)]
NOTE: Use one or all optional parameters as needed to define your configuration. It is not necessary to use any optional parameters.
The following example is a command in which users specify the number of physical disks:
client>smcli 123.45.67.89 -c "create snapshotVirtualDisk sourceVirtualDisk= \"Mars_Spirit_4\" repositoryRAIDLevel=5 repositoryPhysicalDiskCount=3;"
The command in this example creates a new snapshot repository virtual disk that consists of three physical disks. The three physical disks comprise a new disk group with a RAID level of 5. This command also takes a snapshot of the source virtual disk, which starts the copy-on-write operation.
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The following example is the script file version of the command:
create snapshotVirtualDisk sourceVirtualDisk= "Mars_Spirit_4" repositoryRAIDLevel=5 repositoryPhysicalDiskCount=3;

User-Defined Parameters

Parameters for the create snapshotVirtualDisk command enable you to define the snapshot virtual disk to suit the requirements of your storage array. The following table lists the parameters and descriptions of Snapshot Virtual Disk.
Table 11. Snapshot Virtual Disk Parameters
Parameter Description
physicalDiskType
repositoryDiskGroup
freeCapacityArea
userLabel
Specifies the type of physical disk to use for the snapshot repository virtual disk. The type must be specified as Serial Attached SCSI (SAS). This parameter works only with the count-based repository method of defining a snapshot virtual disk.
Specifies the disk group in which to build the snapshot virtual disk. Default builds the snapshot repository virtual disk in the same disk group as the source virtual disk.
Specifies the amount of storage space to use for the snapshot repository virtual disk. Free storage space is defined in units of bytes, kilobytes, megabytes, or gigabytes.
Specifies the name to give to the snapshot virtual disk. If you do not choose a name for the snapshot virtual disk, the RAID controller modules create a default name using the source virtual disk name. For example, if the source virtual disk name is Mars_Spirit_4 and it does not have a snapshot virtual disk, the default snapshot virtual disk name is Mars_Spirit_4‑1. If the source virtual disk already has n – 1 number of snapshot virtual disks, the default name is Mars_Spirit_4‑n.
repositoryUserLabel
Specifies the name to give to the snapshot repository virtual disk. If you do not choose a name for the snapshot repository virtual disk, the RAID controller modules create a default name using the source virtual disk name. For example, if the source virtual disk name is Mars_Spirit_4 and it does not have an associated snapshot repository virtual disk, the default snapshot repository virtual disk name is Mars_Spirit_4‑R1. If the source virtual disk already has n – 1 number of snapshot repository virtual disks, the default name is Mars_Spirit_4‑Rn.
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Parameter Description
warningThresholdPercent
repositoryPercentOfSource
repositoryFullPolicy
enableSchedule
Specifies how full to allow the snapshot repository virtual disk to get before sending a warning that the snapshot repository virtual disk is close to capacity. The warning value is a percentage of the total capacity of the snapshot repository virtual disk. The default value is 50, which represents 50 percent of total capacity. (Change this value using the set snapshotVirtualDisk command.)
Specifies the size of the snapshot repository virtual disk as a percentage of the source virtual disk size. The default value is 20, which represents 20 percent of the source virtual disk size.
Specifies how snapshot processing continues if the snapshot repository virtual disk is full. You can choose to fail writes to the source virtual disk (failSourceWrites) or fail writes to the snapshot virtual disk (failSnapShot). The default value is failSnapShot.
Turns on or off the ability to schedule a snapshot operation. To turn on snapshot scheduling, set the parameter to TRUE. To turn off snapshot scheduling, set the parameter to FALSE. Schedules a snapshot operation of the following type:
• immediate
• startDate
• scheduleDay
• startTime
• scheduleInterval
• endDate
• noEndDate
• timesPerDay
• timeZone
The following example of the create sourceVirtualDisk command includes user‑defined parameters:
client>smcli 123.45.67.89 -c "create snapshotVirtualDisk sourceVirtualDisk= \"Mars_Spirit_4\" repositoryRAIDLevel=5 repositoryPhysicalDiskCount=5 physicalDiskType= SAS userLabel=\"Mars_Spirit_4_snap1\" repositoryUserLabel=\"Mars_Spirit_4_rep1\" warningThresholdPercent=75 repositoryPercentOfSource=40 repositoryFullPolicy= failSnapShot;"enableSchedule=TRUE schedule= (immediate | snapshotSchedule)]
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The following example is the script file version of the command:
create snapshotVirtualDisk sourceVirtualDisk= "Mars_Spirit_4" repositoryRAIDLevel=5 repositoryPhysicalDiskCount=5 physicalDiskType= SAS userLabel="Mars_Spirit_4_snap1" repositoryUserLabel="Mars_Spirit_4_rep1" warningThresholdPercent=75 repositoryPercentOfSource=40 repositoryFullPolicy=failSnapShot;
NOTE: In the previous examples, the names for the snapshot virtual disk and repository virtual disk are defined by the user. If you do not choose to create names for the snapshot virtual disks or the repository virtual disks, the RAID controller modules provide default names. (See Names Of Snapshot Virtual Disks And Repository Virtual Disks for an explanation of naming conventions.)

Names Of Snapshot Virtual Disks And Repository Virtual Disks

The names of snapshot virtual disks and repository virtual disks can be any combination of alphanumeric characters, hyphens, and underscores. The maximum length of the virtual disk names is 30 characters. You must enclose the name in quotation marks. The character string cannot contain a new line. Make sure that you use unique names or the RAID controller module firmware returns an error.
One technique for naming the snapshot virtual disk and the repository virtual disk is to add a hyphenated suffix to the original name of the source virtual disk. The suffix distinguishes between the snapshot virtual disk and the repository virtual disk. For example, if you have a source virtual disk with a name Engineering Data, the snapshot virtual disk can have a name Engineering Data-S1. The repository virtual disk can have a name of Engineering Data‑R1.
If you do not choose a unique name for either the snapshot virtual disk or repository virtual disk, the RAID controller modules create a default name by using the name of the source virtual disk. For example, if the name of the source virtual disk is aaa and it does not have a snapshot virtual disk, then the default name is aaa‑1. If the source virtual disk already has n – 1 number of snapshot virtual disks, then the default name is aaa‑n. Similarly, if the name of the source virtual disk is aaa and it does not have a repository virtual disk, then the default repository virtual disk name is aaa‑R1. If the source virtual disk already has n – 1 number of repository virtual disks, then the default name is aaa-R n.
In the examples from the previous section, the user‑defined name of the snapshot virtual disk was Mars_Spirit_4_snap1. The user‑defined name of the repository virtual disk was Mars_Spirit_4_rep1. The default name provided by the RAID controller module for the snapshot virtual disk would be Mars_Spirit_4-1. The default name provided by the RAID controller module for the repository virtual disk would be Mars_Spirit_4-R1.

Changing Snapshot Virtual Disk Settings

The set (snapshot) virtualDisk command enables you to change the property settings for a snapshot virtual disk. Using this command, you can change the following parameters:
• Name of the snapshot virtual disk
• Warning threshold percent
• Repository full policy
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The following example shows the command to change the name of a snapshot virtual disk:
client>smcli 123.45.67.89 -c "set virtualDisk [\"Mars_Spirit_4-1\"] userLabel=\"Mars_Odyssey_3-2\";"
The following example is the script file version of the command:
set virtualDisk ["Mars_Spirit_4-1"] userLabel= "Mars_Odyssey_3-2";
When you change the warning threshold percent and repository full policy, you can apply the changes to one or several snapshot virtual disks. The following example uses the set (snapshot) virtualDisk command to change these properties on more than one snapshot virtual disk:
client>smcli 123.45.67.89 -c "set virtualDisks [\"Mars_Spirit_4-1\" \"Mars_Spirit_4-2\" \"Mars_Spirit_4-3\"] warningThresholdPercent=50 repositoryFullPolicy=failSourceWrites;"
The following example is the script file version of the command:
set virtualDisks ["Mars_Spirit_4-1" "Mars_Spirit_4-2" "Mars_Spirit_4-3"] warningThresholdPercent=50 repositoryFullPolicy= failSourceWrites;

Stopping And Deleting A Snapshot Virtual Disk

When you create a snapshot virtual disk, copy-on-write immediately starts running. As long as a snapshot virtual disk is enabled, storage array performance is affected by the copy‑on‑write operations to the associated snapshot repository virtual disk. If you no longer want copy-on-write operations to run, you can use the stop snapshot virtualDisk command to stop the copy‑on‑write operations. When you stop a snapshot virtual disk, the snapshot virtual disk and the repository virtual disk are still defined for the source virtual disk; only copy-on-write has stopped. The following example stops a snapshot virtual disk:
client>smcli 123.45.67.89 -c "stop snapshot virtualDisks [\"Mars_Spirit_4-2\" \"Mars_Spirit_4-3\"];"
The following example is the script file version of the command:
stop snapshot virtualDisks ["Mars_Spirit_4-2" "Mars_Spirit_4-3"];
When you stop the copy-on-write operations for a specific snapshot virtual disk, only that snapshot virtual disk is disabled. All other snapshot virtual disks remain in operation.

Re-creating The Snapshot Virtual Disk

To restart a copy-on-write operation, use the recreate snapshot virtualDisk command. This command starts a fresh copy-on-write operation using an existing snapshot virtual disk. When you restart a snapshot virtual disk, the snapshot virtual disk must have either an Optimal or a Disabled state. The following conditions then occur:
• All copy-on-write data previously on the snapshot repository virtual disk is deleted.
• Snapshot virtual disk and snapshot repository virtual disk parameters remain the same as the previously disabled snapshot virtual disk and snapshot repository virtual disk. You can also change the userLabel, warningThresholdPercent, and repositoryFullPolicy parameters when you restart the snapshot virtual disk.
• The original names for the snapshot repository virtual disk are retained.
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Preparing Host Servers To Re-create A Snapshot Virtual Disk

CAUTION: Before you create a new point-in-time image of a source virtual disk, stop any data access (I/O) activity or suspend data transfer to the source virtual disk and snapshot virtual disk to ensure that you capture an accurate point-in-time image of the source virtual disk. Close all applications, including Windows Internet Explorer, to make sure all I/O activity has stopped.
NOTE: Removing the drive letter of the associated virtual disk in Windows or unmounting the virtual drive in Linux helps to guarantee a stable copy of the drive for the Snapshot.
Before re-creating a snapshot virtual disk, both the server and the associated virtual disk you are re‑creating have to be in the proper state. To ensure that the host server is properly prepared to re-create a snapshot virtual disk, you can either use an application to carry out this task, or you can perform the following steps:
1. Stop all I/O activity to the source and snapshot virtual disk (if mounted).
2. Using your Windows system, flush the cache to both the source and the snapshot virtual disk
(if mounted). At the host prompt, type SMrepassist ‑f <filename-identifier> and press <Enter>. See "SMrepassist Utility" in the Owner’s Manual for more information.
3. Remove the drive letter(s) of the source and (if mounted) snapshot virtual disk in Windows or
unmount the virtual drive(s) in Linux to help guarantee a stable copy of the drive for the Snapshot. If this is not done, the snapshot operation reports that it has completed successfully, but the snapshot data is not updated properly.
4. Follow any additional instructions for your operating system. Failure to follow these additional
instructions can create unusable snapshot virtual disks.
NOTE: If your operating system requires additional instructions, you can find those instructions in your operating system documentation.
After your server has been prepared, see Re-creating The Snapshot Virtual Disk to re-create the snapshot virtual disk.

Re-creating A Snapshot Virtual Disk

After first preparing the host server(s) as specified in the preceding procedure, use the following examples to re-create a virtual disk snapshot.
Refer to steps 1 through 4 in the preceding section, Preparing Host Servers To Re-create A Snapshot Virtual Disk. The following example shows the command to restart a snapshot virtual disk:
client>smcli 123.45.67.89 -c "recreate snapshot virtualDisks [\"Mars_Spirit_4-2\" \"Mars_Spirit_4-3\"];"
Refer to steps 1 through 4 in the preceding section, Preparing Host Servers To Re-create A Snapshot Virtual Disk. The following example is the script file version of the command:
recreate snapshot virtualDisks ["Mars_Spirit_4-2" "Mars_Spirit_4-3"];
If you do not intend to use a snapshot virtual disk again, you can delete the snapshot virtual disk using the delete virtualDisk command. When you delete a snapshot virtual disk, the associated snapshot repository virtual disk is also deleted.
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7

Using The Virtual Disk Copy Feature

This chapter describes how the Virtual Disk Copy feature works, lists the script commands for Virtual Disk Copy, and explains how to use the commands to create and run Virtual Disk Copy. Additional information about Virtual Disk Copy and related definitions is available in the online help, the Deployment Guide, the MD Storage Manager online help, and the Administrator's Guide.
NOTE: If you ordered Premium Features for Virtual Disk Copy, you received a Premium Features Activation card shipped in the same box as your Dell PowerVault MD storage array. Follow the directions on the card to obtain a key file and to enable the feature. For more information, see "Premium Feature — Virtual Disk Copy" in the Owner's Manual.
The Virtual Disk Copy feature enables you to copy data from one virtual disk (the source) to another virtual disk (the target) in a single storage array. You can use this feature to perform the following functions:
• Back up data.
• Copy data from disk groups that use smaller capacity physical disks to disk groups using larger capacity physical disks.
• Restore snapshot virtual disk data to the associated source virtual disk.
• Copy data from a thin virtual disk to a standard virtual disk on the same storage array.
NOTE: You cannot copy data from a standard virtual disk to a thin virtual disk.

About Virtual Disk Copy

Starting a virtual disk copy operation does the following to your target copy disks:
• Overwrites all existing data on the target virtual disk.
• Makes the target virtual disk read-only to hosts.
• Fails all snapshot (legacy) virtual disks or snapshot image virtual disks associated with the target virtual disk.
If you have data stored on a virtual disk you specify as a virtual disk copy target, make sure you no longer need the data or have it backed up before beginning virtual disk copy.

Virtual Disk Copy Types

The Virtual Disk Copy script commands create one of following types of virtual disk copies:
• A virtual disk copy using a snapshot (legacy), which suspends I/O to the source virtual disk while the copy is in progress. The source virtual disk will not be available during the copy operation. This is called an offline virtual disk copy.
• A virtual disk copy using a point-in-time copy of any virtual disk, while still allowing access to the source virtual disk when the copy is in progress. This is called an online virtual disk copy.
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In either type of virtual disk copy, the target virtual disk is locked and cannot be accessed while the copy operation is in place.
After completion of the virtual disk copy of a snapshot (legacy), the legacy snapshot is disabled. After completion of the virtual disk copy using a snapshot image, the snapshot image is deleted and the snapshot virtual disk is disabled.
NOTE: You can have a maximum of eight virtual disk copies in progress at one time. If you try to create more than eight virtual disk copies at one time, the RAID controller modules return a status of Pending until one of the virtual disk copies that is in progress finishes and returns a status of Complete.
NOTE: Snapshots created using older (legacy) premium feature versions cannot be managed using newer snapshot premium feature options. Also, a virtual disk in a snapshot group cannot be a target for a virtual disk copy. If you want to choose the base virtual disk of an older (legacy) snapshot virtual disk as your target virtual disk, you must first disable all snapshot (legacy) virtual disks that are associated with the base virtual disk.
The following table lists the Virtual Disk Copy commands.
NOTE: These commands apply when you are using a snapshot or a snapshot (legacy) image.
Table 12. Virtual Disk Copy Commands
Command Description
create virtualDiskCopy
recopy virtualDiskCopy
enable storageArray feature
recopy virtualDiskCopy
remove virtualDiskCopy
set virtualDiskCopy
show virtualDiskCopy
show virtualDiskCopy sourceCandidates
show virtualDiskCopy targetCandidates
stop virtualDiskCopy
Creates a virtual disk copy and starts the virtual disk copy operation.
Reinitiates a virtual disk copy operation using an existing virtual disk copy pair.
Activates the Virtual Disk Copy feature.
Re-initiates a virtual disk copy operation by using an existing virtual disk copy pair.
Removes a virtual disk copy pair.
Defines the properties for a virtual disk copy pair.
Returns information about virtual disk copy operations. You can retrieve information about a specific virtual disk copy pair, or all virtual disk copy pairs in the storage array.
Returns information about the candidate virtual disks that you can use as the source for a virtual disk copy operation.
Returns information about the candidate virtual disks that you can use as the target for a virtual disk copy operation.
Stops a virtual disk copy operation.
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Creating A Virtual Disk Copy

Before creating a virtual disk copy, ensure that a suitable target virtual disk exists on the storage array, or create a new target virtual disk specifically for the virtual disk copy. The target virtual disk must have a capacity equal to or greater than the source virtual disk.
You can have a maximum of eight virtual disk copies in progress at one time. Any virtual disk copy greater than eight has a status of Pending until one of the virtual disk copies with a status of In Progress completes.
The following steps show the general process for creating a virtual disk copy:
1. Enable the Virtual Disk Copy feature.
2. Determine candidates for a virtual disk copy.
3. Create the target virtual disk and source virtual disk for a virtual disk copy.

Enabling The Virtual Disk Copy Feature

The first step in creating a virtual disk copy is to make sure the feature is enabled on the storage array. You need a feature key to enable the feature. To enable the feature key file, use the command:
enable storageArray feature file="filename"
where, the file parameter is the complete file path and file name of a valid feature key file. Enclose the file path and file name in quotation marks (" "). Valid file names for feature key files usually end with a .key extension.

Determining Virtual Disk Copy Candidates

All virtual disks might not be available for use in virtual disk copy operations. To determine which candidate virtual disks on the storage array can be used as a source virtual disk, use the show virtualDiskCopy sourceCandidates command. To determine which candidate virtual disks on the storage array can be used as a target virtual disk, use the command. These commands return a list of the expansion enclosure, slot, and capacity information for source virtual disk and target virtual disk candidates. You can use the show virtualDiskCopy
sourceCandidates
have enabled the virtual disk copy feature.
A source virtual disk can be a standard or thin virtual disk. A target virtual disk can be a standard or thin virtual disk in a disk group or disk pool and, if the legacy version is enabled, a legacy snapshot base virtual disk.
and the show virtualDiskCopy targetCandidates commands only after you
show virtualDiskCopy targetCandidates

Creating A Virtual Disk Copy

CAUTION: A virtual disk copy overwrites data on the target virtual disk. Ensure that you no longer need the data or have backed up the data on the target virtual disk before starting a virtual disk copy.
When you create a virtual disk copy, you must define which virtual disks to use for the source virtual disk and target virtual disks. Define the source virtual disk and target virtual disk by the name of each virtual disk. You can also define the copy priority and choose whether you want the target virtual disk to be write enabled or read only after the data is copied from the source virtual disk.
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Preparing Host Servers To Create A Virtual Disk Copy

CAUTION: Before you create a new copy of a source virtual disk, stop any data access (I/O) activity or suspend data transfer to the source virtual disk (and, if applicable, the target disk) to ensure that you capture an accurate point-in-time image of the source virtual disk. Close all applications, including Windows Internet Explorer, to make sure all I/O activity has stopped.
NOTE: Removing the drive letter of the associated virtual disk(s) in Windows or unmounting the virtual drive in Linux helps to guarantee a stable copy of the drive for the virtual disk copy.
Before creating a virtual disk copy, both the server and the associated virtual disk you are copying have to be in the proper state. To ensure that the host server is properly prepared to create a virtual disk copy, you can either use an application to carry out this task, or you can perform the following steps:
1. Stop all I/O activity to the source and target virtual disk.
2. Using your Windows system, flush the cache to both the source and the target virtual disk (if
mounted). At the host prompt, type SMrepassist -f <filename-identifier> and press <Enter>.
See "SMrepassist Utility" in the Owner’s Manual for more information.
3. Remove the drive letter(s) of the source and (if mounted) virtual disk in Windows or unmount the
virtual drive(s) in Linux to help guarantee a stable copy of the drive for the virtual disk. If this is not done, the copy operation reports that it has completed successfully, but the copied data is not updated properly.
4. Follow any additional instructions for your operating system. Failure to follow these additional
instructions can create unusable virtual disk copies.
NOTE: If your operating system requires additional instructions, you can find those instructions in your operating system documentation.
After your server has been prepared, see Copying The Virtual Disk to copy the virtual disk.

Copying The Virtual Disk

After first preparing the host server(s) as specified in the preceding procedure, use the following examples to make a virtual disk copy.
The following syntax is the general form of the command:
create virtualDiskCopy source="sourceName" target= "targetName" [copyPriority=(highest | high | medium | low | lowest) targetReadOnlyEnabled=(TRUE | FALSE)]
NOTE: Use one or both of the optional parameters as needed to help define your configuration. It is not necessary to use any optional parameters.
Once the virtual disk copy has started, the source virtual disk is read only to all I/O activity. Any write attempts to the source virtual disk fails until the operation completes.
Once the virtual disk copy operation is completed register the target virtual disk with the operating system to be used by performing the following steps:
• Enable write permission on the target virtual disk by either removing the Virtual Disk Copy Pair or explicitly setting write permission.
– In Windows, assign a drive letter to the virtual disk.
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– In Linux, mount the virtual disk.
See step 1 to step 4 in Preparing Host Servers To Create A Virtual Disk Copy.
The create virtualDiskCopy command might look like the following example:
client>smcli 123.45.67.89 -c "create virtualDiskcopy source=\"Jaba_Hut\" target= \"Obi_1\" copyPriority=medium targetreadonlyenabled=true"
The command in this example copies the data from the source virtual disk named Jaba_Hut to the target virtual disk named Obi_1. Setting the copy priority to medium provides a compromise between the following storage array operations:
• The speed with which the data is copied from the source virtual disk to the target virtual disk
• The amount of processing resource required for data transfers to other virtual disks in the storage array
Setting the targetReadOnlyEnabled parameter to TRUE means that write requests cannot be made to the target virtual disk. This setting also ensures that the data on the target virtual disk remains unaltered.
Refer to steps 1 through 4 in the preceding section, Preparing Host Servers To Create A Virtual Disk Copy. The following example is the script file version of the command:
create virtualDiskcopy source="Jaba_Hut" target= "Obi_1" copyPriority=medium targetreadonlyenabled=true;
After the virtual disk copy operation is completed, the target virtual disk automatically becomes read-only to the hosts. Any write requests to the target virtual disk are rejected, unless you disable the read-only attribute. Use the set virtualDiskCopy command to disable the read-only attribute.

Viewing Virtual Disk Copy Properties

Using the show virtualDiskCopy command, you can view information about one or more selected source virtual disks or target virtual disks. This command returns the following information:
• The virtual disk role (target or source)
• The copy status
• The start timestamp
• The completion timestamp
• The virtual disk copy priority
• The read-only attribute setting for the target virtual disk
• The source virtual disk World Wide Identifier (WWID) or the target virtual disk WWID
A virtual disk can be a source virtual disk for one virtual disk copy and a target virtual disk for another virtual disk copy. If a virtual disk participates in more than one virtual disk copy, the details are repeated for each associated copy pair.
The following syntax is the general form of the command:
show virtualDiskCopy (allVirtualDisks | source [sourceName] | target [targetName])
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The following example shows a command that returns information about a virtual disk used for a virtual disk copy:
client>smcli 123.45.67.89 -c "show virtualDiskCopy source [\"Jaba_Hut\"];"
The command in the preceding example requests information about the source virtual disk Jaba_Hut. If you want information about all virtual disks, use the allVirtualDisks parameter. You can also request information about a specific target virtual disk.
The following example is the script file version of the command:
show virtualDiskCopy source ["Jaba_Hut"];

Changing Virtual Disk Copy Settings

The set virtualDiskCopy command enables you to change the property settings for a virtual disk copy pair. Using this command, you can change the following items:
• Copy priority
• Read/write permission for the target virtual disk
Copy priority has five relative settings, which range from highest to lowest. The highest priority supports the virtual disk copy, but I/O activity might be affected. The lowest priority supports I/O activity, but the virtual disk copy takes longer. You can change the copy priority at three different times in the operation:
• Before the virtual disk copy begins
• While the virtual disk copy has a status of In Progress
• After the virtual disk copy has completed re-creating a virtual disk copy using the recopy
virtualDiskCopy
command
When you create a virtual disk copy pair and after the original virtual disk copy has completed, the target virtual disk is automatically defined as read-only to the hosts. The read-only status of the target virtual disk ensures that the copied data on the target virtual disk is not corrupted by additional writes to the target virtual disk after the virtual disk copy is created. Maintain the read-only status when the following conditions apply:
• You are using the target virtual disk for backup purposes
• You are copying data from one disk group to a larger disk group for greater accessibility
• You are planning to use the data on the target virtual disk to copy back to the source virtual disk in case of a disabled or failed snapshot virtual disk
At other times you might want to write additional data to the target virtual disk. You can use the set virtualDiskCopy command to reset the read/write permission for the target virtual disk.
NOTE: If you enabled host writes to the target virtual disk, read and write requests are rejected while the virtual disk copy has a status of In Progress, Pending, or Failed.
The following syntax is the general form of the command:
set virtualDiskCopy target [targetName] [source [sourceName]] copyPriority=(highest | high | medium | low | lowest) targetReadOnlyEnabled=(TRUE | FALSE)
NOTE: Use one or both of the parameters as needed to help define your configuration. It is not necessary to use either parameter.
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The following example shows how to change parameters using the set virtualDiskCopy command:
client>smcli 123.45.67.89 -c "set virtualDiskcopy target [\"Obi_1\"] copyPriority=highest targetreadonlyenabled=false;"
The following example is the script file version of the command:
set virtualDiskcopy target ["Obi_1"] copyPriority= highest targetreadonlyenabled=false;

Recopying A Virtual Disk

CAUTION: The recopy virtualDiskCopy command overwrites existing data on the target virtual disk and makes the target virtual disk read‑only to hosts. The command fails all snapshot virtual disks associated with the target virtual disk, if any exist.
Using the recopy virtualDiskCopy command, you can create a new virtual disk copy for a previously defined copy pair that has a status of Stopped, Failed, or Completed. Use the recopy
virtualDiskCopy
for off-site storage. When using the recopy virtualDiskCopy command to make a backup, you cannot write to source while the recopy is running. The recopy might take a long time.
When you run the recopy virtualDiskCopy command, the data on the source virtual disk is copied in its entirety to the target virtual disk.
Reset the copy priority for the recopy operation by using the recopy virtualDiskCopy command. The higher priorities allocate storage array resources to the virtual disk copy at the expense of storage array performance.
command to create backups of the target virtual disk, then copy the backup to tape
recopy virtualDiskCopy

Preparing Host Servers To Recopy A Virtual Disk

CAUTION: Before you create a new copy of a source virtual disk, stop any data access (I/O) activity or suspend data transfer to the source virtual disk (and, if applicable, the target disk) to ensure that you capture an accurate point-in-time image of the source virtual disk. Close all applications, including Windows Internet Explorer, to make sure all I/O activity has stopped.
NOTE: Removing the drive letter of the associated virtual disk(s) in Windows or unmounting the virtual drive in Linux helps to guarantee a stable copy of the drive for the virtual disk copy.
Before creating a new virtual disk copy for an existing copy pair, both the server and the associated virtual disk you are recopying have to be in the proper state. To ensure that the host server is properly prepared to create a virtual disk recopy, you can either use an application to carry out this task, or you can perform the following steps:
1. Stop all I/O activity to the source and target virtual disk.
2. Using your Windows system, flush the cache to both the source and the target virtual disk (if
mounted). At the host prompt, type SMrepassist -f <filename-identifier> and press <Enter>.
See "SMrepassist Utility" in the Owner’s Manual for more information.
3. Remove the drive letter(s) of the source and (if mounted) virtual disk in Windows or unmount the
virtual drive(s) in Linux to help guarantee a stable copy of the drive for the virtual disk. If this is not done, the copy operation reports that it has completed successfully, but the copied data is not updated properly.
4. Follow any additional instructions for your operating system. Failure to follow these additional
instructions can create unusable virtual disk copies.
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NOTE: If your operating system requires additional instructions, you can find those instructions in your operating system documentation.
After your server has been prepared, see Recopying The Virtual Disk to recopy the virtual disk.

Recopying The Virtual Disk

After first preparing the host server(s) as specified in the preceding procedure, use the following examples to make a virtual disk copy.
The following syntax is the general form of the command:
recopy virtualDiskCopy target [targetName] [source [sourceName] copyPriority=(highest | high | medium | low | lowest) targetReadOnlyEnabled=(TRUE | FALSE)]
NOTE: Use one or all of the optional parameters as needed to help define your configuration. It is not necessary to use any optional parameters.
Refer to steps 1 through 4 in the preceding section, Preparing Host Servers To Recopy A Virtual Disk. The following example shows a command that changes the copy priority:
client>smcli 123.45.67.89 -c "recopy virtualDiskCopy target [\"Obi_1\"] copyPriority=highest;"
The command in this example copies data from the source virtual disk associated with the target virtual disk Obi_1 to the target virtual disk again. The copy priority is set to the highest value to complete the virtual disk copy as quickly as possible. The underlying consideration for using this command is that you have already created the virtual disk copy pair. When you create a virtual disk copy pair, you automatically created one virtual disk copy. Using this command, you are copying the data from the source virtual disk to the target virtual disk. You are making this copy because the data on the source virtual disk changed since the previous copy was made.
Refer to steps 1 through 4 in the preceding section, Preparing Host Servers To Recopy A Virtual Disk. The following example is the script file version of the command:
recopy virtualDiskCopy target ["Obi_1"] copyPriority=highest;

Stopping A Virtual Disk Copy

The stop virtualDiskCopy command enables you to stop a virtual disk copy that has a status of In Progress, Pending, or Failed. After you stop a virtual disk copy, you can use the virtualDiskCopy command to create a new virtual disk copy using the original virtual disk copy pair. All mapped hosts have write access to the source virtual disk.
The following syntax is the general form of the command:
stop virtualDiskCopy target [targetName] [source [sourceName]]
The following example shows a command to stop a virtual disk copy operation:
client>smcli 123.45.67.89 -c "stop virtualDiskCopy target [\"Obi_1\"];"
The following example is the script file version of the command:
stop virtualDiskCopy target ["Obi_1"];
recopy
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Removing Copy Pairs

The remove virtualDiskCopy command enables you to remove a virtual disk copy pair from the storage array configuration. All virtual disk copy information for the source virtual disk and target virtual disk is removed from the storage array configuration. The data on the source virtual disk or target virtual disk is not deleted. Removing a virtual disk copy from the storage array configuration also removes the read-only attribute for the target virtual disk.
CAUTION: If the virtual disk copy has a status of In Progress, you must stop the virtual disk copy before you can remove the virtual disk copy pair from the storage array configuration.
The following syntax is the general form of the command:
remove virtualDiskCopy target [targetName] [source [sourceName]]
The following example shows a command to remove a virtual disk copy pair:
client>smcli 123.45.67.89 -c "remove virtualDiskCopy target [\"Obi_1\"];"
The following example is the script file version of the command:
remove virtualDiskCopy target ["Obi_1"];

Interaction With Other Features

You can run the Virtual Disk Copy feature while running the following features:
• Storage Partitioning
• Snapshot Virtual Disks
When running the Virtual Disk Copy feature with other features, you must take the requirements of other features into consideration to ensure you set up a stable storage array configuration. You can also run the Virtual Disk Copy feature while running Dynamic Virtual Disk Expansion.

About Snapshot (Legacy) Premium Features With Virtual Disk Copy

• A source virtual disk for a virtual disk copy can be a standard virtual disk or a thin virtual disk (if supported in your firmware version).
• A target virtual disk can be a standard virtual disk in a disk group or disk pool, or a snapshot (legacy) base virtual disk if the snapshot (legacy) premium feature is the only snapshot premium feature enabled on your storage array. A virtual disk in a snapshot group cannot be a virtual disk copy target.
• Snapshots created using the older (legacy) premium feature versions cannot be managed using newer snapshot premium feature options.
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Using The Remote Replication Premium Feature

The following types of Remote Replication premium features are supported on the MD storage array:
8
Remote Replication
Remote Replication (Legacy)
NOTE: This chapter describes the standard Remote Replication premium feature supported in both iSCSI and Fibre Channel storage arrays only. To understand the Remote Replication (legacy) premium feature, see Using The Remote Replication (Legacy) Premium Feature.
The Remote Replication premium feature provides for online, real-time replication of data between storage arrays over a remote distance. In the event of a disaster or a catastrophic failure on one storage array, you can promote the second storage array to take over responsibility for computing services. Remote Replication is designed for extended storage environments in which the storage arrays that are used for Remote Replication are maintained at separate sites.
You can use Remote Replication for these functions:
Disaster recovery
Standard asynchronous replication using point-in-time images to batch the resynchronization between the local and remote site. This type of replication is supported on either Fibre Channel or iSCSI storage arrays (both local and remote arrays must have the same data protocol).
Synchronous (or full-write) replication that synchronizes local and remote site data in real-time. This type of replication is supported on Fibre Channel storage arrays only.
Remote Replication lets you replicate data from one site to another site, which provides an exact duplicate at the remote (secondary) site. If the primary site fails, you can use replicated data at the remote site for failover and recovery. You can then shift storage operations to the remote site for continued operation of all of the services that are usually provided by the primary site.
Data vaulting and data availability
Two-way data protection
Remote Replication lets you send data off site where it can be protected. You can then use the off-site copy for testing or to act as a source for a full backup to avoid interrupting operations at the primary site.
Remote Replication provides the ability to have two storage arrays back up each other by duplicating critical virtual disks on each storage array to virtual disks on the other storage array. This action lets each storage array recover data from the other storage array in the event of any service interruptions.

How Remote Replication Works

Standard Remote Replication (asynchronous) is a premium feature that provides RAID controller-based data replication between a local and remote storage array on a per-virtual disk basis. By identifying
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primary (local) and secondary (remote) virtual disk pairs, called replicated pairs, write operations to the primary virtual disk of the pair are tracked by the RAID controller firmware and captured in a point-in­time image and transferred to the secondary virtual disk in the pair.
Remote Replication groups allow you to manage synchronization of both virtual disks to create a consistent data set across local and remote storage arrays. Point-in-time images on the primary virtual disk and the secondary virtual disk can be resynchronized in a batch approach that increases replication throughput. When data synchronization completes, the system uses the point-in-time images on the secondary virtual disk to ensure that the data is maintained in a consistent state during subsequent synchronization operations to the secondary virtual disk.

Replication Pairs And Replication Repositories

Replicated pairs, comprising of a primary and secondary virtual disk, contain identical data copies as a result of data synchronization. Replication repository virtual disks are used to manage replication data synchronization and are required for both the primary virtual disk and secondary virtual disk in a replicated pair.
A replication repository consists of the following data:
• Resynchronization and recovery point images for primary and secondary virtual disks.
• Tracking data from the primary virtual disk that occurs in between synchronization intervals. This data is also written to the secondary virtual disk in case a reversal of the primary/secondary virtual disk role should occur.

Differences Between Remote Replication And Remote Replication (Legacy) Features

The standard Remote Replication premium feature uses a point-in-time snapshot image to capture the state of the source virtual disk and only writes data that has changed since the last point-in-time image. The Remote Replication (Legacy) premium feature reproduces every data write to the local (primary) virtual disk on the remote (secondary) virtual disk through a Fibre Channel-only connected configuration. While not producing a fully synchronized data view between both storage arrays, standard Remote Replication offers a much faster replication solution that can run on both iSCSI and Fibre Channel configurations.
NOTE: Both remote and local storage arrays must of the same data protocol. Replication between Fibre Channel and iSCSI storage arrays is not supported.
Standard Remote Replication creates a repository virtual disk for each replicated pair, increasing throughput between local and remote arrays. Remote Replication (Legacy) uses a single repository virtual disk for all replicated pairs.
Physical distance between local and remote storage arrays is unlimited using the Standard Remote Replication premium feature. Remote Replication (legacy) is limited to approximately 10 Km (6.2 miles) between local and remote storage arrays.

Link Interruptions Or Secondary Virtual Disk Errors

When processing write requests, the primary RAID controller module might be able to write to the primary virtual disk, but a link interruption might prevent communication with the remote (secondary) RAID controller module.
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In this case, the remote write operation cannot be completed to the secondary virtual disk, and the primary virtual disk and the secondary virtual disk are no longer correctly replicated. The primary RAID controller module transitions the replicated pair into an Unsynchronized state and sends an I/O completion to the primary host. The primary host can continue to write to the primary virtual disk, but remote writes do not take place.
When communication is restored between the RAID controller module owner of the primary virtual disk and the RAID controller module owner of the secondary virtual disk, a resynchronization takes place. This resynchronization happens automatically, or it must be started manually, depending on which write mode you chose when setting up the replication relationship. During the resynchronization, only the blocks of data that have changed on the primary virtual disk during the link interruption are copied to the secondary virtual disk. After the resynchronization starts, the replicated pair transitions from an Unsynchronized status to a Synchronization in Progress status.
The primary RAID controller module also marks the replicated pair as unsynchronized when a virtual disk error on the secondary side prevents the remote write from completing. For example, an offline secondary virtual disk or a failed secondary virtual disk can cause the remote replication to become unsynchronized. When the virtual disk error is corrected (the secondary virtual disk is placed online or recovered to an Optimal status), then synchronization is required. The replicated pair then transitions to a Synchronization in Progress status.

Resynchronization

Data replication between the primary virtual disk and the secondary virtual disk in a replication relationship is managed by the RAID controller modules and is transparent to host machines and applications. When the RAID controller module owner of the primary virtual disk receives a write request from a host, the RAID controller module first logs information about the write to a replication repository virtual disk. The RAID controller module then writes the data to the primary virtual disk. The RAID controller module then initiates a write operation to copy the affected data to the secondary virtual disk on the remote storage array.
If a link interruption or a virtual disk error prevents communication with the secondary storage array, the RAID controller module owner of the primary virtual disk transitions the replicated pair into an Unsynchronized status. The RAID controller module owner then sends an I/O completion to the host sending the write request. The host can continue to issue write requests to the primary virtual disk, but remote writes to the secondary virtual disk do not take place.
When connectivity is restored between the RAID controller module owner of the primary virtual disk and the RAID controller module owner of the secondary virtual disk, the virtual disks must be resynchronized by copying the blocks of data that changed during the interruption to the secondary virtual disk. Only the blocks of data that have changed on the primary virtual disk during the link interruption are copied to the secondary virtual disk.
CAUTION: Possible loss of data access – Any communication disruptions between the primary storage array and the secondary storage array while resynchronization is underway could result in a mix of new data and old data on the secondary virtual disk. This condition would render the data unusable in a disaster recovery situation.
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Remote Replication Group

After your Remote Replication premium feature is activated on both local and remote storage arrays, you must create Remote Replication groups on the local storage array.
A replication group contains at least one replicated virtual disk pair, one on the local storage and one on the remote storage array, that share data synchronization settings. Multiple replicated pairs can reside in a replication group, but each pair can only be a member of one Remote Replication group.
The following attributes also apply to a Remote Replication group:
• The local storage array serves as the primary side of the Remote Replication group, while the remote storage array serves as the secondary side of the Remote Replication group.
• At the virtual disk level, all virtual disks added to the Remote Replication group on the local storage array serve as the primary role in the Remote Replication configuration. Virtual disks added to the group on the remote storage array serve the secondary role.
Once you have selected virtual disks at both the remote and local storage array that you want to pair in a replication relationship, adding them to a replication group actually begins the replication synchronization process.
For more detailed information on the role of Remote Replication groups, see the Administrator's Guide.

Previous Users Of Remote Replication (Legacy) Premium Feature

If you have upgraded (or plan to upgrade) your RAID controller firmware version to a level that supports both legacy and non-legacy Remote Replication, any legacy replication configurations you have previously set up will be unaffected, and will continue to function normally.

Remote Replication Requirements And Restrictions

To use the standard Remote Replication premium feature, you must have:
• Two storage arrays with write access and both these storage arrays must have sufficient space to replicate data between them.
• Each storage must have a dual-controller Fibre Channel or iSCSI configuration (single-controller configurations are not supported).
• Fibre Channel Connection Requirements — You must attach dedicated remote replication ports to a Fibre Channel fabric environment. In addition, these ports must support the Name Service.
• You can use a fabric configuration that is dedicated solely to the remote replication ports on each RAID controller module. In this case, host systems can connect to the storage arrays using fabric.
• Fibre Channel Arbitrated Loop (FC-AL), or point-to-point configurations, are not supported for array­to-array communications.
• Maximum distance between the local site and remote site is 10 km (6.2 miles), using single-mode fibre Gigabit interface converters (GBICs) and optical long-wave GBICs.
• iSCSI connection considerations:
– iSCSI does not require dedicated ports for replication data traffic – iSCSI array-to-array communication must use a host-connected port (not the Ethernet
management port).
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– The first port that successfully establishes an iSCSI connection is used for all subsequent
communication with that remote storage array. If that connection subsequently fails, a new session is attempted using any available ports.

Primary And Secondary Virtual Disks

Before you create any replication relationships, virtual disks must exist at both the primary site and the secondary site. The virtual disk that resides on the local storage array is the primary virtual disk. Similarly, the virtual disk that resides on the remote storage array is the secondary virtual disk. If neither the primary virtual disk nor the secondary virtual disk exist, you must create these virtual disks. Keep these guidelines in mind when you create the secondary virtual disk:
• The secondary virtual disk must be of equal or greater size than the primary virtual disk.
• The RAID level of the secondary virtual disk does not have to be the same as the primary virtual disk.

Setting Up Remote Replication

Setting up Remote Replication between local and remote storage arrays consists of the following:
• Enabling Remote Replication (on both storage arrays)
• Activating the Remote Replication premium feature on both the local and remote storage arrays.
• Creating a Remote Replication group on the local storage array.
• Adding a replicated pair of virtual disks to the Remote Replication group.

Enabling The Remote Replication Premium Feature

The first step in creating a remote replication is to make sure that the Remote Replication premium feature is enabled on both storage arrays. Because Remote Replication is a premium feature, you need a feature key file to enable the premium feature. The command for enabling the feature key file is as follows:
enable storageArray feature file=”asyncReplicationactivation_key”
In this command, asyncReplication is literal and is appended with the activation_key, which is provided by Dell. For example, if your activation key value is 999999:
enable storageArray feature file="asyncReplication999999"

Activating The Remote Replication Premium Feature

Activating the Remote Replication premium feature prepares the storage arrays to create and configure replication relationships. After you activate the premium feature, the secondary ports for each RAID controller module are reserved and dedicated to remote replication use. In addition, replication repository virtual disks are automatically created for each RAID controller module in the storage array.
To activate the Remote Replication premium feature, use this command:
activate storageArray feature=asyncReplication

Creating A Remote Replication Group

The first step in establishing a Remote Replication relationship is to create a replication group on the local storage array. A replication group cannot be created on the remote storage array.
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The create asyncRemoteReplicationGroup command creates a new, empty remote replication group on both the local storage array and the remote storage array. Each replicated pair you add to the remote replication group share the same synchronization settings, primary and secondary role, and write mode.
This command must be run on the local storage array. Remote replication group creation is initiated from the storage array that contains the virtual disks that hold the primary role in the replicate relationship. The following command create a replication group names RRG-001 on a remote iSCSI storage array named Remote_SS_A101. The remote storage array has a password of 123Dell321 (remotePassword=). A warning will be triggered when the capacity of a replication repository virtual disk reaches 75 percent of capacity (warningThresholdPercent=).
create asyncRemoteReplicationGroup userLabel="RRG-001" remoteStorageArrayName="Remote_SS_A101" interfaceType=iSCSI remotePassword="123Dell321" warningThresholdPercent=75;

Adding Primary Virtual Disk To Remote Replication Group

The add virtualDisk command adds a primary virtual disk to a remote replication group. This command is valid only on the local storage array that contains the remote replication group to which you want to add the primary virtual disk. To add the secondary virtual disk on the remote storage array to the remote replication group, use the
You have two options for specifying a repository virtual disk when using this command: you can either specify an existing repository virtual disk or create a new one when running the command.
To add a virtual disk named employeeBackfilData to the Remote_SS_A101 group you created using an existing repository virtual disk named rep_VD_404:
add virtualDisk="employeeBackfilData" asyncRemoteReplicationGroup="Remote_SS_A101" repositoryVirtualDisk="rep_VD_404";
establish asyncRemoteReplication virtualDisk command.
To add the same virtual disk to the same replication, but create a new 10GB repository virtual disk from an existing disk group named DG_09:
add virtualDisk="employeeBackfilData" asyncRemoteReplicationGroup="Remote_SS_A101" repositoryVirtualDisk=DG_09 capacity=10GB;
You can substitute a disk pool name for the disk group name, if creating the repository virtual disk from disk pool space.

Changing Remote Replication Group Settings

The set asyncRemoteReplicationGroup command lets you change settings for an existing replication group.
The following parameters set synchronization and warning threshold values for the replication group. Changing the synchronization settings affects the synchronization operations of all replicated pairs within the remote replication group.
• syncInterval
• warningSyncThreshold
• warningRecoveryThreshold
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• warningThresholdPercent
The following parameters allow you to change (or force) the primary/secondary role of a replication group, or whether or not to perform a synchronization before changing primary/secondary roles.
• role
• force
• nosync
You can apply the changes to one or several remote replicated pairs by using this command. Use the primary virtual disk name to identify the remote replicated pairs for which you are changing the properties.
The full command syntax is shown below:
set asyncRemoteReplicationGroup ["asyncRemoteReplicationGroupName"] [syncInterval=integer (minutes | hours | days) warningSyncThreshold=integer (minutes | hours | days) warningRecoveryThreshold= warningThresholdPercent=percentValue autoResync=(TRUE | FALSE) virtualDisk="virtualDiskName" increaseRepositoryCapacity (repositoryVirtualDisk="repos_xxxx" | repositoryVirtualDisk=(diskGroupName [capacity=capacityValue]) repositoryVirtualDisk=(diskPoolName [capacity=capacityValue])) role=(primary| secondary) ([force=TRUE|FALSE]|[noSync=TRUE|FALSE])
integer (minutes | hours | days)

Adding Secondary Virtual Disk To Remote Replication Group

Use the establish asyncRemoteReplication command to add the secondary virtual disk on the remote storage array to the replication group. This command completes the remote replicated pair process begun with the storage array to the replication group.
Before running this command, the remote replication group must exist and the primary virtual disk must exist in the remote replication group. After the establish asyncRemoteReplication command successfully completes, remote replication automatically starts between the primary virtual disk and the secondary virtual disk.
Using the previous example, the following command completes a replicated pair within a replication group named Remote_SS_A101 between the primary virtual disk (on the local storage array) named
employeeBackfilData and a secondary virtual disk (on the remote storage array) named employeeBackfilData_remote:
establish asyncRemoteReplication virtualDisk="employeeBackFilData_remote" asyncRemoteReplicationGroup="Remote_SS_A101" primaryVirtualDisk="employeeBackfilData";
add virtualDisk command, which added the primary virtual disk on the local

Suspending A Remote Replication Group

Use the asyncRemoteReplicationGroup command to stop data transfer between a primary virtual disk and a secondary virtual disk in a replication relationship without disabling the replication relationship. Suspending a replication relationship group lets you control when the data on the primary virtual disk and data on the secondary virtual disk are synchronized. Suspending a replication relationship group helps to
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reduce any performance impact to the host application that might occur while any changed data on the primary virtual disk is copied to the secondary virtual disk.
When a replication relationship is in a suspended state, the primary virtual disk does not make any attempt to contact the secondary virtual disk. Any writes to the primary virtual disk are persistently logged in the replication repository virtual disks. After the replication relationship resumes, any data that is written to the primary virtual disk is automatically written to the secondary virtual disk. Only the modified data blocks on the primary virtual disk are written to the secondary virtual disk. Full synchronization is not required.
This example shows the suspend remoteReplicationGroup command:
suspend asyncRemoteReplicationGroup ["asyncRemoteReplicationGroupName"];
The replication relationship group remains suspended until you use the resume asyncRemoteReplicationGroup command to restart synchronization activities.
This example shows the resume remoteReplicationGroup command:
resume asyncRemoteReplicationGroup ["asyncRemoteReplicationGroupName"];

Deleting A Remote Replication Group

Use the delete asyncRemoteReplicationGroup command to delete one or more replication groups from the local or remote storage array. The replication group you are attempting to delete must be empty (contain no virtual disks or replicated pairs) before running this command.
This example shows the delete asyncRemoteReplicationGroup command:
c:\...\smX\client>smcli 123.45.67.88 123.45.67.89
-c delete asyncRemoteReplicationGroup["replication_group_name"];
To delete all replication groups from the local and remote storage arrays, use the delete
allAsyncRemoteReplicationGroups
To delete selected replication groups, separate group names with "":
delete asyncRemoteReplicationGroups ["name1""name2"];
command.

Removing A Virtual Disk Or Repository Virtual Disk From A Remote Replication Group

Use the remove virtualDisk command to remove either a member virtual disk or repository virtual disk from an existing replication group. This command can only be run on the local storage array containing the replication group affected by the command.
The command shown below removes diskname from the replication group named groupname. Using the optional deleteRepositoryMembers parameter with a value of TRUE also delete the repository virtual disk members:
remove virtualDisk ["diskname"] asyncRemoteReplicationGroup="groupname" deleteRepositoryMembers=TRUE;
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Disabling The Remote Replication Premium Feature

You disable the Remote Replication premium feature to prevent the new replication relationship from being created. When you disable the Remote Replication premium feature, the premium feature is in a Disabled/Active state. In this state, you can maintain and manage previously existing replication relationships; however, you cannot create new relationships. To disable the Remote Replication premium feature, use this command:
disable storageArray feature=asyncReplication;

Deactivating The Remote Replication Premium Feature

If you no longer require the Remote Replication premium feature and you have removed all of the replication relationships (replication groups and replicated pairs), you can deactivate the premium feature. Deactivating the premium feature re-establishes the normal use of dedicated ports on both storage arrays and deletes replication repository virtual disks. To deactivate the Remote Replication premium feature, use this command:
deactivate storageArray feature=asyncReplication;

Interaction With Other Premium Features

You can run the Remote Replication premium feature while running these premium features:
• Snapshot—both standard Snapshot and Snapshot (legacy) premium features
• Virtual Disk Copy
When you run the Remote Replication (legacy) premium feature with other premium features, you must consider the requirements of the other premium features to ensure that you set up a stable storage array configuration.
For more information on using Remote Replication with other premium features, see the Administrator's Guide.

Standard Remote Replication Commands

The following Remote Replication commands are also available. For more information, see Commands
Listed Alphabetically.
Table 13. Standard Remote Replication Commands
Command Description
stop asyncRemoteReplicationGroup rolechange
check asyncRemoteReplicationGroup repositoryConsistency
clear asyncRemoteReplicationFault
check storageArray connectivity
Cancels a pending primary/secondary storage array role reversal.
Reports information on data in the repository virtual disks.
Clears an remote replication "sticky" fault from a replication group(s) and/or member virtual disk.
Verifies the local and the remote storage arrays have a valid communication path.
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Command Description
remove asyncRemoteReplicationGroup incompleteRemoteReplication
reset storageArray arvmStats reset storageArray iscsiIpAddress
show asyncRemoteReplicationGroup synchronizationProgress
show asyncRemoteReplicationGroup summary
Removes an orphaned replicated pair virtual disk.
Resets IP address for the remote storage array to re-establish connection with the local storage array or resets synchronization statistics for member virtual disks to relative 0.
Shows progress of periodic synchronization of the replication group as a percentage.
Shows configuration information for one or more replication groups.
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9

Using The Remote Replication (Legacy) Premium Feature

The Remote Replication (legacy) premium feature provides for online, real-time replication of data between storage arrays over a remote distance. In the event of a disaster or a catastrophic failure on one storage array, you can promote the second storage array to take over responsibility for computing services. Remote Replication (legacy) is designed for extended storage environments in which the storage arrays that are used for Remote Replication (legacy) are maintained at separate sites. Virtual disks on one storage array are replicated to virtual disks on another storage array across a fabric SAN. Data transfers can be synchronous or asynchronous. You choose the method when you set up the remote replicated pair. The data transfers occur at Fibre Channel speeds to maintain data on the different storage arrays. Because Remote Replication (legacy) is storage based, it does not require any server overhead or application overhead.
You can use Remote Replication (legacy) for these functions:
Disaster recovery
Data vaulting and data availability
Two-way data protection
Remote Replication (legacy) lets you replicate data from one site to another site, which provides an exact duplicate at the remote (secondary) site. If the primary site fails, you can use replicated data at the remote site for failover and recovery. You can then shift storage operations to the remote site for continued operation of all of the services that are usually provided by the primary site.
Remote Replication (legacy) lets you send data off site where it can be protected. You can then use the off-site copy for testing or to act as a source for a full backup to avoid interrupting operations at the primary site.
Remote Replication (legacy) provides the ability to have two storage arrays back up each other by duplicating critical virtual disks on each storage array to virtual disks on the other storage array. This action lets each storage array recover data from the other storage array in the event of any service interruptions.

How Remote Replication (Legacy) Works

When you create a remote replicated pair, the remote replicated pair consists of a primary virtual disk on a local storage array and a secondary virtual disk on a storage array at another site. A standard virtual disk might only be included in one replicated virtual disk pair.
The primary virtual disk is the virtual disk that accepts host I/O activity and stores application data. When the replication relationship is first created, data from the primary virtual disk is copied in its entirety to the secondary virtual disk. This process is known as a full synchronization and is directed by the RAID controller module owner of the primary virtual disk. During a full synchronization, the primary virtual disk remains fully accessible for all normal I/O operations.
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The RAID controller module owner of the primary virtual disk initiates remote writes to the secondary virtual disk to keep the data on the two virtual disks synchronized.
The secondary virtual disk maintains a replication (or copy) of the data on its associated primary virtual disk. The RAID controller module owner of the secondary virtual disk receives remote writes from the RAID controller module owner of the primary virtual disk but will not accept host write requests. Hosts are able to read from the secondary virtual disk, which appears as read-only.
In the event of a disaster or a catastrophic failure at the primary site, you can perform a role reversal to promote the secondary virtual disk to a primary role. Hosts then are able to read from and write to the newly promoted virtual disk, and business operations can continue.

Replication Repository Virtual Disks

A replication repository virtual disk is a special virtual disk in the storage array that is created as a resource for the RAID controller module owner of the primary virtual disk in a remote replicated pair. The RAID controller module stores replication information on this virtual disk, including information about remote writes that are not yet complete. The RAID controller module can use this information to recover from RAID controller module resets and the accidental powering down of the storage arrays.
When you activate the Remote Replication (legacy) premium feature on the storage array, you create two replication repository virtual disks, one for each RAID controller module in the storage array. An individual replication repository virtual disk is not needed for each remote replication.
When you create the replication repository virtual disks, you specify the location of the virtual disks. You can either use existing free capacity, or you can create a disk group for the virtual disks from unconfigured capacity and then specify the RAID level.
Because of the critical nature of the data being stored, do not use RAID Level 0 as the RAID level of replication repository virtual disks. The required size of each virtual disk is 128 MB, or 256 MB total for both replication repository virtual disks of a dual-RAID controller module storage array. In previous versions of the Remote Replication (legacy) premium feature, the replication repository virtual disks required less disk storage space and needed to be upgraded to use the maximum amount of replication relationships.

Replication Relationships

Before you create a replication relationship, you must enable the Remote Replication (legacy) premium feature on both the primary storage array and the secondary storage array. You must also create a secondary virtual disk on the secondary site if one does not already exist. The secondary virtual disk must be a standard virtual disk of equal or greater capacity than the associated primary virtual disk.
When secondary virtual disks are available, you can establish a replication relationship in the MD storage management software by identifying the primary virtual disk and the storage array that contains the secondary virtual disk.
When you first create the replication relationship, a full synchronization automatically occurs, with data from the primary virtual disk copied in its entirety to the secondary virtual disk.
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Data Replication

The RAID controller modules manage data replication between the primary virtual disk and the secondary virtual disk. This process is transparent to host machines and applications. This section describes how data is replicated between the storage arrays that are participating in Remote Replication (legacy). This section also describes the actions taken by the RAID controller module owner of the primary virtual disk if a link interruption occurs between storage arrays.
Write Modes
When the RAID controller module owner of the primary virtual disk receives a write request from a host, the RAID controller module first logs information about the write to a replication repository virtual disk, and then writes the data to the primary virtual disk. The RAID controller module then initiates a remote write operation to copy the affected data blocks to the secondary virtual disk at the secondary storage array.
The Remote Replication (legacy) premium feature provides two write mode options that affect when the I/O completion indication is sent back to the host: Synchronous and Asynchronous.
Synchronous Write Mode
Synchronous write mode provides the highest level security for full data recovery from the secondary storage array in the event of a disaster. Synchronous write mode does reduce host I/O performance. When this write mode is selected, host write requests are written to the primary virtual disk and then copied to the secondary virtual disk. After the host write request has been written to the primary virtual disk and the data has been successfully copied to the secondary virtual disk, the RAID controller module removes the log record on the replication repository virtual disk. The RAID controller module then sends an I/O completion indication back to the host system. Synchronous write mode is selected as the default value and is the recommended write mode.
Asynchronous Write Mode
Asynchronous write mode offers faster host I/O performance but does not guarantee that a copy operation has successfully completed before processing the next write request. When you use Asynchronous write mode, host write requests are written to the primary virtual disk. The RAID controller module then sends an “I/O complete” indication back to the host system, without acknowledging that the data has been successfully copied to the secondary (remote) storage array.
When using Asynchronous write mode, write requests are not guaranteed to be completed in the same order on the secondary virtual disk as they are on the primary virtual disk. If the order of write requests is not retained, data on the secondary virtual disk might become inconsistent with the data on the primary virtual disk. This event could jeopardize any attempt to recover data if a disaster occurs on the primary storage array.
Write Consistency Mode
When multiple replication relationships exist on a single storage array and have been configured to use Asynchronous write mode and to preserve consistent write order, they are considered to be an interdependent group that is in the Write consistency mode. The data on the secondary, remote storage array cannot be considered fully synchronized until all of the remote replications that are in the Write consistency mode are synchronized.
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If one replication relationship in the group becomes unsynchronized, all of the replication relationships in the group become unsynchronized. Any write activity to the remote, secondary storage arrays is prevented to protect the consistency of the remote data set.

Link Interruptions Or Secondary Virtual Disk Errors

When processing write requests, the primary RAID controller module might be able to write to the primary virtual disk, but a link interruption might prevent communication with the remote (secondary) RAID controller module.
In this case, the remote write operation cannot be completed to the secondary virtual disk, and the primary virtual disk and the secondary virtual disk are no longer correctly replicated. The primary RAID controller module transitions the replicated pair into an Unsynchronized state and sends an I/O completion to the primary host. The primary host can continue to write to the primary virtual disk, but remote writes do not take place.
When communication is restored between the RAID controller module owner of the primary virtual disk and the RAID controller module owner of the secondary virtual disk, a resynchronization takes place. This resynchronization happens automatically, or it must be started manually, depending on which write mode you chose when setting up the replication relationship. During the resynchronization, only the blocks of data that have changed on the primary virtual disk during the link interruption are copied to the secondary virtual disk. After the resynchronization starts, the replicated pair transitions from an Unsynchronized status to a Synchronization in Progress status.
The primary RAID controller module also marks the replicated pair as unsynchronized when a virtual disk error on the secondary side prevents the remote write from completing. For example, an offline secondary virtual disk or a failed secondary virtual disk can cause the remote replication to become unsynchronized. When the virtual disk error is corrected (the secondary virtual disk is placed online or recovered to an Optimal status), then synchronization is required. The replicated pair then transitions to a Synchronization in Progress status.

Resynchronization

Data replication between the primary virtual disk and the secondary virtual disk in a replication relationship is managed by the RAID controller modules and is transparent to host machines and applications. When the RAID controller module owner of the primary virtual disk receives a write request from a host, the RAID controller module first logs information about the write to a replication repository virtual disk. The RAID controller module then writes the data to the primary virtual disk. The RAID controller module then initiates a write operation to copy the affected data to the secondary virtual disk on the remote storage array.
If a link interruption or a virtual disk error prevents communication with the secondary storage array, the RAID controller module owner of the primary virtual disk transitions the replicated pair into an Unsynchronized status. The RAID controller module owner then sends an I/O completion to the host sending the write request. The host can continue to issue write requests to the primary virtual disk, but remote writes to the secondary virtual disk do not take place.
When connectivity is restored between the RAID controller module owner of the primary virtual disk and the RAID controller module owner of the secondary virtual disk, the virtual disks must be resynchronized by copying the blocks of data that changed during the interruption to the secondary virtual disk. Only the
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