Dell PowerEdge R7525, PowerEdge R6525 User Manual
Dell Technologies PowerEdge RAID
Controller 11 User’s Guide
PERC H755 adapter, H755 front SAS, and H755N
front NVMe
Par t N umb er: UC PA- 110 1, UCPF-1100, and UCPF-1110
Sep tem ber 20 20
Rev . A 00
Notes, cautions, and warnings
NOTE: A NOTE indicates important information that helps you make better use of your product.
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.
© 2020 Dell Inc. or its subsidiaries. All rights reserved. Dell, EM C, and other trademarks are trademarks of Dell Inc. or its subsidiaries. Oth er
trademarks may be trademarks of their respective owners.
Contents
Chapter 1: Dell Technologies PowerEdge RAID Controller 11.......................................................... 8
Features of PERC H755 adapter..................................................................................................................................... 9
Features of PERC H755 front SAS.................................................................................................................................9
Features of PERC H755N front NVMe........................................................................................................................ 10
Technical specifications of PERC 11 cards................................................................................................................... 11
Operating systems supported by PERC 11....................................................................................................................11
Chapter 2: Applications and User Interfaces supported by PERC 11..............................................13
Comprehensive Embedded Management ................................................................................................................... 13
Dell OpenManage Storage Management......................................................................................................................13
Human Interface Infrastructure Configuration Utility............................................................................................... 13
The PERC Command Line Interface..............................................................................................................................14
Chapter 3: Features of PowerEdge RAID Controller 11..................................................................15
Controller features.............................................................................................................................................................15
Non-Volatile Memory Express...................................................................................................................................15
Opal Security Management....................................................................................................................................... 16
Hardware Root of Trust ............................................................................................................................................ 16
1 MB I/O......................................................................................................................................................................... 16
Auto Configure RAID 0............................................................................................................................................... 16
Disk roaming.................................................................................................................................................................. 16
FastPath......................................................................................................................................................................... 17
Non–RAID disks............................................................................................................................................................ 17
Physical disk power management.............................................................................................................................17
Profile Management.....................................................................................................................................................17
Secure firmware update............................................................................................................................................. 18
Snapdump...................................................................................................................................................................... 18
Virtual disk features...........................................................................................................................................................18
Virtual disk write cache policy...................................................................................................................................18
Virtual disk read cache policy.................................................................................................................................... 19
Virtual disk migration...................................................................................................................................................19
Virtual disk initialization.............................................................................................................................................. 19
Reconfiguration of virtual disks............................................................................................................................... 20
Background operations.............................................................................................................................................. 22
Hard drive features........................................................................................................................................................... 22
Self-Encrypting Disks................................................................................................................................................. 22
Instant secure erase....................................................................................................................................................23
4 KB sector disk drives...............................................................................................................................................23
Fault tolerance................................................................................................................................................................... 23
The SMART feature.................................................................................................................................................... 23
Patrol Read................................................................................................................................................................... 24
Physical disk failure detection.................................................................................................................................. 24
Controller cache.......................................................................................................................................................... 25
Battery Transparent Learn Cycle............................................................................................................................ 26
Contents 3
Chapter 4: Install and remove a PERC 11 card.............................................................................. 27
Safety instructions............................................................................................................................................................ 27
Before working inside your system............................................................................................................................... 27
After working inside your system.................................................................................................................................. 28
Remove the PERC H755 adapter..................................................................................................................................28
Install the PERC H755 adapter...................................................................................................................................... 29
Remove the PERC H755 front SAS card.................................................................................................................... 30
Install the PERC H755 front SAS card......................................................................................................................... 31
Remove the PERC H755N front NVMe card............................................................................................................. 32
Install the PERC H755N front NVMe card................................................................................................................. 34
Chapter 5: Driver support for PERC 11 ........................................................................................36
Creating the device driver media.................................................................................................................................. 36
Download and save PERC 11 drivers from the support site..............................................................................36
Download and save PERC 11 drivers from the Dell Systems Service and Diagnostic Tools .................... 36
Windows driver installation............................................................................................................................................. 37
Install PERC 11 driver while newly installing the Windows Server 2016 and later........................................37
Install PERC 11 driver on which the Windows Server 2016 is already installed and later...........................37
Update PERC 11 driver that runs on Windows Server 2016 and later............................................................ 38
Linux driver installation.................................................................................................................................................... 38
Install or update a RPM driver package using the KMOD support..................................................................39
Install or update a RPM driver package using the KMP support..................................................................... 39
Loading the driver while installing an operating system.......................................................................................... 40
Chapter 6: Firmware.................................................................................................................... 41
Install the PERC 11 firmware using Dell Update Package (DUP)............................................................................41
Chapter 7: Manage PERC 11 controllers using HII configuration utility......................................... 42
Enter the PERC 11 HII configuration utility..................................................................................................................42
Exit the PERC 11 HII configuration utility.....................................................................................................................42
Navigate to Dell PERC 11 configuration utility............................................................................................................43
View the HII Configuration utility dashboard.............................................................................................................. 43
Configuration management.............................................................................................................................................44
Auto Configure RAID 0...............................................................................................................................................44
Create virtual disks......................................................................................................................................................44
Create profile based virtual disk.............................................................................................................................. 45
View disk group properties........................................................................................................................................46
Convert to Non–RAID disk........................................................................................................................................46
Delete configurations..................................................................................................................................................46
Controller management....................................................................................................................................................47
Clear controller events............................................................................................................................................... 47
Save controller events................................................................................................................................................47
Save debug log............................................................................................................................................................. 47
Enable security............................................................................................................................................................. 47
Disable security............................................................................................................................................................ 47
Change security settings........................................................................................................................................... 48
Restore factory default settings..............................................................................................................................48
Auto configure behavior............................................................................................................................................ 48
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Contents
Manage controller profile...........................................................................................................................................48
Advanced controller properties................................................................................................................................49
Virtual disk management................................................................................................................................................. 52
Virtual disk numbering................................................................................................................................................52
Configure Virtual Disks...............................................................................................................................................54
Perform expand virtual disk operation................................................................................................................... 54
Perform consistency check...................................................................................................................................... 54
Physical disk management.............................................................................................................................................. 55
View physical disk properties................................................................................................................................... 55
Cryptographic erase................................................................................................................................................... 56
Physical disk erase...................................................................................................................................................... 56
Assigning a global hot spare......................................................................................................................................57
Assigning a dedicated hot spare.............................................................................................................................. 57
Convert to Non–RAID disk........................................................................................................................................58
Hardware components.....................................................................................................................................................58
View battery properties............................................................................................................................................. 58
View physical disks associated with an enclosure...............................................................................................59
Security key management in HII configuration utility...............................................................................................59
Chapter 8: Security key and RAID management............................................................................61
Security key implementation........................................................................................................................................... 61
Local Key Management.................................................................................................................................................... 61
Create a security key........................................................................................................................................................ 61
Change Security Settings................................................................................................................................................62
Disable security key.......................................................................................................................................................... 62
Create a secured virtual disk.......................................................................................................................................... 63
Secure a pre-existing Non–RAID disk.......................................................................................................................... 63
Secure a pre-existing virtual disk.................................................................................................................................. 63
Import a secured virtual disk.......................................................................................................................................... 63
Dell Technologies OpenManage Secure Enterprise Key Manager........................................................................ 64
Supported controllers for OpenManage Secure Enterprise Key Manager.................................................... 64
Manage enterprise key manager mode.................................................................................................................. 64
Disable enterprise key manager mode....................................................................................................................64
Manage virtual disks in enterprise key manager mode...................................................................................... 65
Manage non–RAID disks in enterprise key manager mode............................................................................... 65
Migration of drives from local key management to enterprise key management........................................65
Chapter 9: Troubleshooting.........................................................................................................66
Single virtual disk performance or latency in hypervisor configurations............................................................. 66
Configured disks removed or not accessible error message.................................................................................. 66
Dirty cache data error message..................................................................................................................................... 67
Discovery error message................................................................................................................................................. 67
Drive Configuration Changes Error Message............................................................................................................. 67
Windows operating system installation errors .......................................................................................................... 68
Firmware fault state error message............................................................................................................................. 68
Foreign configuration found error message................................................................................................................68
Foreign configuration not found in HII error message............................................................................................. 68
Degraded state of virtual disks...................................................................................................................................... 68
Memory errors................................................................................................................................................................... 68
Contents
5
Preserved Cache State....................................................................................................................................................69
Security key errors............................................................................................................................................................69
Secured foreign import errors.................................................................................................................................. 69
Failure to select or configure non Self-Encrypting Disks non-SED................................................................ 69
Failure to delete security key....................................................................................................................................69
Failure of Cryptographic Erase task on secured physical disks........................................................................70
General issues.................................................................................................................................................................... 70
PERC card has yellow bang in Windows operating system device manager................................................ 70
PERC card not seen in operating systems............................................................................................................ 70
Physical disk issues........................................................................................................................................................... 70
Physical disk in failed state....................................................................................................................................... 70
Unable to rebuild a fault tolerant virtual disk........................................................................................................70
Fatal error or data corruption reported..................................................................................................................70
Multiple disks are inaccessible...................................................................................................................................71
Rebuilding data for a failed physical disk................................................................................................................ 71
Virtual disk fails during rebuild using a global hot spare......................................................................................71
Dedicated hot spare disk fails during rebuild......................................................................................................... 71
Redundant virtual disk fails during reconstruction.............................................................................................. 72
Virtual disk fails rebuild using a dedicated hot spare.......................................................................................... 72
Physical disk takes a long time to rebuild.............................................................................................................. 72
Drive removal and insertion in the same slot generates a foreign configuration event ............................72
SMART errors.....................................................................................................................................................................72
Smart error detected on a non–RAID disk............................................................................................................ 72
Smart error detected on a physical disk in a non–redundant virtual disk......................................................73
Smart error detected on a physical disk in a redundant virtual disk............................................................... 73
Replace member errors....................................................................................................................................................73
Source disk fails during replace member operation.............................................................................................73
Target disk fails during replace member operation............................................................................................. 74
A member disk failure is reported in the virtual disk which undergoes replace member operation........ 74
Linux operating system errors........................................................................................................................................ 74
Virtual disk policy is assumed as write-through error message....................................................................... 74
Unable to register SCSI device error message.....................................................................................................74
Drive indicator codes........................................................................................................................................................75
HII error messages............................................................................................................................................................ 75
Unhealthy Status of the Drivers.............................................................................................................................. 75
Rebuilding a drive during full initialization.............................................................................................................. 76
Chapter 10: Appendix RAID description........................................................................................77
Summary of RAID levels...................................................................................................................................................77
RAID terminology...............................................................................................................................................................78
Disk striping...................................................................................................................................................................78
Disk mirroring................................................................................................................................................................78
Spanned RAID levels................................................................................................................................................... 78
Parity data..................................................................................................................................................................... 79
Chapter 11: Getting help.............................................................................................................. 80
Recycling or End-of-Life service information............................................................................................................ 80
Contacting Dell.................................................................................................................................................................. 80
Locating the Express Service Code and Service Tag.............................................................................................. 80
6
Contents
Receiving automated support with SupportAssist ................................................................................................... 81
Chapter 12: Documentation resources......................................................................................... 82
Contents 7
Dell Technologies PowerEdge RAID
Controller 11
Dell Technologies PowerEdge RAID Controller 11, or PERC 11 is a series of RAID disk array controllers made by Dell for its
PowerEdge servers. The PERC 11 series consists of the PERC H755 adapter, PERC H755 front SAS, and PERC H755N front
NVMe cards which have the following characteristics:
● Provides reliability, high performance, and fault-tolerant disk subsystem management
● Offers RAID control capabilities including support for RAID levels 0, 1, 5, 6, 10, 50, 60
● Complies with Serial Attached SCSI (SAS) 3.0 providing up to 12 Gb/sec throughput
● Supports Dell-qualified Serial Attached SCSI (SAS), SATA hard drives, Solid State Drive (SSD), and PCIe SSD (NVMe)
● Supported drive speeds for NVMe drives are 8 GT/s and 16 GT/s
NOTE: Mixing disks of different speed (7,200 rpm, 11,000 rpm, or 15,000 rpm) and bandwidth (3 Gbps, 6 Gbps, or 12 Gbps)
while maintaining the same drive type (SAS or SATA) and technology (HDD or SSD) is supported.
NOTE: Mixing SAS, SATA, and NVMe drives in a virtual disk is not supported, and mixing HDD and SSD in a virtual disk is
not supported.
NOTE: For the safety, regulatory, and ergonomic information associated with these devices, and for more information
about the Integrated Dell Remote Access Controller (iDRAC) or Lifecycle Controller (LC) remote management, see your
platform documentation.
1
Topics:
• Features of PERC H755 adapter
• Features of PERC H755 front SAS
• Features of PERC H755N front NVMe
• Technical specifications of PERC 11 cards
• Operating systems supported by PERC 11
8 Dell Technologies PowerEdge RAID Controller 11
Features of PERC H755 adapter
Figure 1. Features of PERC H755 adapter
Heatsink 2. PCIe connector
1.
3. Battery 4. Backplane connector A
5. Backplane connector B 6. Battery cable connector
Features of PERC H755 front SAS
Figure 2. Features of PERC H755 front SAS
1.
Battery 2. PCIe input connector
3. Power card edge connector 4. Heatsink
5. Backplane connector A 6. Backplane connector B
Dell Technologies PowerEdge RAID Controller 11 9
7. Battery cable connector
Features of PERC H755N front NVMe
Figure 3. Features of PERC H755N front NVMe
Battery 2. PCIe cable connector
1.
3. Power card edge connector 4. Heatsink
5. Backplane connector A 6. Backplane connector B
7. Battery cable connector
10 Dell Technologies PowerEdge RAID Controller 11
Technical specifications of PERC 11 cards
The table below lists and describes the different PERC 11 cards series and their specifications:
Table 1. Technical specifications of PERC 11 cards
Feature PERC H755 adapter PERC H755 front SAS PERC H755N front NVMe
RAID levels 0, 1, 5, 6, 10, 50 ,60 0, 1, 5, 6, 10, 50, 60 0, 1, 5, 6, 10, 50, 60
Non–RAID Yes Yes Yes
Enclosures per port Not applicable Not applicable Not applicable
Processor Broadcom RAID-on-chip,
SAS3916 chipset
Battery backup unit Yes Yes Yes
Local Key Management
security
Secure enterprise key
manager security
Non-volatile cache Yes Yes Yes
Cache memory 8 GB DDR4 2666 MT/s cache 8 GB DDR4 2666 MT/s cache 8 GB DDR4 2666 MT/s cache
Cache function Write back, write through, no
Max no of PDs in RAID mode 240 240 240
Max no of VDs in RAID mode 240 240 240
Max no of VDs per disk group 16 16 16
Hot swap devices supported Yes Yes Yes
Hardware XOR engine Yes Yes Yes
Online capacity expansion Yes Yes Yes
Dedicated and global hot
spare
Yes Yes Yes
Yes Yes Yes
read ahead, and read ahead
Yes Yes Yes
Broadcom RAID-on-chip,
SAS3916 chipset
Write back, write through, no
read ahead, and read ahead
Broadcom RAID-on-chip,
SAS3916 chipset
Write back, write through, no
read ahead, and read ahead
Drives types 3 Gbps SATA, 6 Gbps
SATA/SAS, and 12 Gbps SAS,
Gen3 (8 GT/s), and Gen4 (16
GT/s) NVMe
VD strip size 64 KB, 128 KB, 256 KB, 512
KB, 1 MB
PCIe support Gen 4 Gen 4 Gen 4
NOTE: PERC H755 adapter supports either SAS, SATA, or NVMe drives depending on the backplane/server configuration.
NOTE: PERC controller supports only conventional magnetic recording (CMR) drives, and does not support shingled
magnetic recording (SMR) drives.
NOTE: PERC H755 family of controllers currently does not support SEKM on firmware version 52.13.2-3661.
3 Gbps SATA, 6 Gbps
SATA/SAS, and 12 Gbps SAS
64 KB, 128 KB, 256 KB, 512
KB, 1 MB
Gen3 (8 GT/s) and Gen4 (16
GT/s) NVMe
64 KB, 128 KB, 256 KB, 512
KB, 1 MB
Operating systems supported by PERC 11
See Dell Technologies Enterprise operating systems support for a list of supported operating systems by a specific server for
the PERC 11 card.
Dell Technologies PowerEdge RAID Controller 11
11
NOTE: For the latest list of supported operating systems and driver installation instructions, see the operating system
documentation at www.dell.com/operatingsystemmanuals. For specific operating system service pack requirements, see
the Drivers and Downloads section at www.dell.com/manuals.
12 Dell Technologies PowerEdge RAID Controller 11
2
Applications and User Interfaces supported
by PERC 11
PERC 11 card Management applications include the Comprehensive Embedded Management (CEM), Dell OpenManage Storage
Management, The Human Interface Infrastructure (HII) configuration utility, and The PERC Command Line Interface (CLI). They
enable you to manage and configure the RAID system, create and manage multiple disk groups, control and monitor multiple
RAID systems, and provide online maintenance.
Topics:
• Comprehensive Embedded Management
• Dell OpenManage Storage Management
• Human Interface Infrastructure Configuration Utility
• The PERC Command Line Interface
Comprehensive Embedded Management
Comprehensive Embedded Management (CEM) is a storage management solution for Dell systems that enables you to monitor
the RAID and network controllers installed on the system using iDRAC without an operating system installed on the system.
Using CEM enables you to do the following:
● Monitor devices with and without an operating systems installed on the system
● Provide a specific location to access monitored data of the storage devices and network cards
● Allows controller configuration for all PERC 11 cards
NOTE:
If you boot the system to HII (F2) or Lifecycle Controller (F10), then you cannot view the PERC cards on the CEM
UI. The PERC cards are displayed on the CEM UI only after the system boot is complete.
NOTE: It is not recommended that you create more than 8 VDs simultaneously with CEM.
Dell OpenManage Storage Management
Dell OpenManage Storage Management is a storage management application for Dell systems that provides enhanced features
for configuring locally attached RAID disk storage. The Dell OpenManage storage management application enables you to
perform controller and enclosure functions for all supported RAID controllers and enclosures from a single graphical or Command
Line Interface (CLI). The User Interface (UI) is wizard-driven with features for novice and advanced users, and detailed online
help. Using the Dell OpenManage storage management application, you can protect your data by configuring data-redundancy,
assigning hot spares, or rebuilding failed physical disks. The fully featured CLI, which is available on select operating systems,
allows you to perform RAID management tasks either directly from the console or through scripting.
For more information, see the Dell OpenManage Storage Management User's Guide at www.dell.com/
NOTE:
openmanagemanuals.
Human Interface Infrastructure Configuration Utility
The Human Interface Infrastructure (HII) configuration utility is a storage management application integrated into the system
BIOS <F2>. It is used to configure and manage your Dell PowerEdge RAID Controller (PERC) virtual disks, and physical disks.
This utility is independent of the operating system.
NOTE: The BIOS configuration utility <Ctrl> <R> is not supported on PERC 11 cards.
Applications and User Interfaces supported by PERC 11 13
The PERC Command Line Interface
The PERC Command Line Interface (CLI) is a storage management application. This utility allows you to set up, configure, and
manage your Dell PowerEdge RAID Controller (PERC) by using the Command Line Interface (CLI).
NOTE: For more information, see Dell EMC PowerEdge RAID Controller CLI Reference Guide at www.dell.com/
storagecontrollermanuals.
14 Applications and User Interfaces supported by PERC 11
3
Features of PowerEdge RAID Controller 11
Topics:
• Controller features
• Virtual disk features
• Hard drive features
• Fault tolerance
Controller features
This section lists the following controller features supported on Dell Technologies PowerEdge RAID Controller 11 cards in detail:
● Non-Volatile Memory Express
● Opal Security Management
● Hardware Root of Trust
● 1 MB I/O
● Auto Configure RAID 0
● Disk roaming
● FastPath
● Non–RAID disks
● Physical disk power management
● Profile Management
● Secure firmware update
● Snapdump
Non-Volatile Memory Express
Non-Volatile Memory Express (NVMe) is a standardized, high-performance host controller interface and a storage protocol for
communicating with non-volatile memory storage devices over the peripheral component interconnect express (PCIe) interface
standard. The PERC 11 controller supports up to 8 direct-attach NVMe drives. The PERC 11 controller is a PCIe endpoint to the
host, a PowerEdge server, and configured as a PCIe root complex for downstream PCIe NVMe devices connected to the
controller.
NOTE:
The NVMe drive on the PERC 11 controller shows up as a SCSI disk in the operating system, and the NVMe
command line interface will not work for the attached NVMe drives.
Conditions under which a PERC supports an NVMe drive
● In NVMe devices the namespace identifier (NSID) with ID 1, which is (NSID=1) must be present.
● In NVMe devices with multiple namespace(s), you can use the drive capacity of the namespace with NSID=1.
● The namespace with NSID=1 must be formatted without protection information and cannot have the metadata enabled.
● PERC supports 512-bytes or 4 KB sector disk drives for NVMe devices.
Features of PowerEdge RAID Controller 11 15
Opal Security Management
Opal Security Management of Opal SED drives requires security key management support. You can use the application software
or The Integrated Dell Remote Access Controller (iDRAC) to generate the security key that is set in the Opal drives and used as
an authentication key to lock and unlock the Opal drives.
Hardware Root of Trust
Hardware RoT (RoT) builds a chain of trust by authenticating all the firmware components prior to its execution, and it permits
only the authenticated firmware to perform and be flashed. The controller boots from an internal boot ROM (IBR) that
establishes the initial root of trust and this process authenticates and builds a chain of trust with succeeding software using this
root of trust.
1 MB I/O
PERC 11 controllers support a 1 MB I/O feature; if the capacity of I/O frame is greater than 1 MB, the I/O frame is broken into
smaller chunks.
Auto Configure RAID 0
Auto Configure RAID 0 feature creates a single drive RAID 0 on each physical disk that is in the ready state. For more
information, see Auto Configure RAID 0 on page 44.
Auto Configure behavior
Auto configure behavior automatically configures unconfigured drives during reboot and hot insertion. As per the setting,
unconfigured drives will be configured as per the option; but the configured drives will remain unaffected. PERC 11 supports Off
and Non–RAID settings.
Table 2. Auto configure behavior settings
Settings Description
Off Auto configure behavior is turned off
Non–RAID Unconfigured drives are configured as non–RAID disk during boot or during hot insertion; all the
configured drives will remain unaffected
Off to Non–RAID disk Unconfigured drives are converted to non–RAID disk; all the configured drives will remain unaffected
Non–RAID disk to Off Unconfigured drives remain unconfigured good; all the configured drives will remain unaffected
Disk roaming
Disk roaming is when a physical disk is moved from one cable connection or backplane slot to another on the same controller.
The controller automatically recognizes the relocated physical disks and logically places them in the virtual disks that are part of
the disk group. If the physical disk is configured as a non–RAID disk, then the relocated physical disk is recognized as a non–
RAID disk by the controller.
CAUTION: It is recommended that you perform disk roaming when the system is turned off.
CAUTION: Do not attempt disk roaming during RAID level migration (RLM) or online capacity expansion (OCE).
This causes loss of the virtual disk.
16 Features of PowerEdge RAID Controller 11
Using disk roaming
About this task
Perform the following steps to use disk roaming:
Steps
1. Turn off the power to the system, physical disks, enclosures, and system components.
2. Disconnect power cables from the system.
3. Move the physical disks to desired positions on the backplane or the enclosure.
4. Perform a safety check. Make sure the physical disks are inserted properly.
5. Turn on the system.
Results
The controller detects the RAID configuration from the configuration data on the physical disks.
FastPath
FastPath is a feature that improves application performance by delivering high I/O per second (IOPs) for solid state drives
(SSD). The PERC 11 series of cards support FastPath.
To enable FastPath on a virtual disk, the cache policies of the RAID controller must be set to write-through and no read ahead.
This enables FastPath to use the proper data path through the controller based on command (read/write), I/O size, and RAID
type.
Non–RAID disks
A non–RAID disk is a single disk to the host, and not a RAID volume. The only supported cache policy for non–RAID disks is
Write-Through.
Physical disk power management
Physical disk power management is a power-saving feature of PERC 11 series cards. The feature allows disks to be spun down
based on disk configuration and I/O activity. The feature is supported on all rotating SAS and SATA disks, and includes
unconfigured and hot-spare disks. The physical disk power management feature is disabled by default. You can enable the
feature in the Dell Open Manage Storage Management application or in the Human Interface Infrastructure (HII) configuration
utility. For more information on HII configuration and physical disk power management, see Enabling physical disk power
management. For more information on using the Dell Open Manage Storage Management application, see the Dell OpenManage
documentation at www.dell.com/openmanagemanuals.
Profile Management
PERC 11 supports the PD240 profile. It defines controller queue depth and the maximum number of physical and virtual disks.
Table 3. Supported profile on PERC 11
Feature PD240
Profile ID 30
Maximum physical disk supported 240
Maximum virtual disk supported 240
Controller queue depth 5120
Features of PowerEdge RAID Controller 11 17
Secure firmware update
This feature provides a cryptographic method of updating the firmware using an RSA encryption-decryption algorithm.
Only Dell-certified firmware is supported on your PERC controller.
Snapdump
The Snapdump feature provides the Dell support team with the debug information which can help to find the cause of firmware
failure. In the instance of firmware failures, the firmware collects the logs and information at the time of failure, which are
stored in a compressed file called a snapdump.
Snapdumps are also generated manually to provide additional debug information. When a snapdump is generated, it is stored in
the controller's cache memory. This means in the event of a power loss the controller will offload the snapdump as part of its
cache preservation mechanism. Snapdumps are preserved by default through four reboots before its deleted.
To generate a snapdump, change the snapdump, delete a snapdump, and to download a stored snapdump settings, see Dell
EMC PowerEdge RAID Controller CLI Reference Guide at www.dell.com/storagecontrollermanuals.
Virtual disk features
This section lists the following virtual disk features supported on PERC 11 cards in detail:
● Virtual disk write cache policy
● Virtual disk read cache policy
● Virtual disk migration
● Virtual disk initialization
● Reconfiguration of virtual disk
● Background operations
Virtual disk write cache policy
The write cache policy of a virtual disk determines how the controller handles writes to the virtual disk.
Table 4. Write cache policies
Feature Description
Write-back The controller sends a data transfer completion signal to the host when the controller cache
has received all the data in a transaction. The controller then writes the cached data to the
storage device in the background.
NOTE: The default cache setting for virtual disks is Write-back caching. Write-back
caching is also supported for single drive RAID 0 virtual disks.
Write-through The controller sends a data transfer completion signal to the host system when the disk
subsystem has received all the data in a transaction.
NOTE: Certain data patterns and configurations perform better with a write-through
cache policy.
NOTE: All RAID volumes are presented as write-through to the operating system (Windows and Linux) independent of the
actual write cache policy of the virtual disk. PERC cards manage the data in cache independently of the operating system or
any applications.
NOTE: Use the Dell OpenManage storage management application or the HII Configuration Utility to view and manage
virtual disk cache settings.
Conditions under which write-back is employed
Write-back caching is used under all conditions in which the battery is present and in good condition.
18
Features of PowerEdge RAID Controller 11
Conditions under which forced write-back with no battery is employed
CAUTION: It is recommended that you use a power backup system when forcing write-back to ensure there is no
loss of data if the system suddenly loses power.
Write-back mode is available when you select force write-back with no battery. When forced write-back mode is selected, the
virtual disk is in write-back mode even if the battery is not present.
Virtual disk read cache policy
The read policy of a virtual disk determines how the controller handles reads to that virtual disk.
Table 5. Read policies
Feature Description
Read ahead Allows the controller to read sequentially ahead of requested data and to store the additional data in
cache memory, anticipating that the data is required soon. This speeds up reads for sequential data,
but there is slight improvement when accessing random data.
No read ahead Disables the read ahead capability.
NOTE: Adaptive read ahead is no longer supported. Selecting adaptive read ahead is equivalent to selecting the read ahead
option.
Virtual disk migration
The PERC 11 series supports migration of virtual disks from one controller to another without taking the target controller offline.
The controller can import RAID virtual disks in optimal, degraded, or partially degraded states. You cannot import a virtual disk
that is offline. When a controller detects a configured physical disk, it marks the physical disk as foreign, and generates an alert
indicating that a foreign disk was detected.
Disk migration pointers:
● Supports migration of virtual disks from PERC H345, H740P, H745, H745P MX, and H840 to the PERC 11 series except for
H345.
● Supports migration of volumes created within the PERC 11 series.
● Does not support migration from the PERC 11 series to PERC H345, H740P, H745, H745P MX, and H840.
● Does not support migration from PERC H330, H730, and H830 to the PERC 11 series.
NOTE: The source controller must be offline prior to performing the disk migration.
NOTE: Importing non–RAID drives and uneven span RAID 10 virtual disks from PERC 9 to PERC 11 is not supported.
NOTE: Disks cannot be migrated to older generations of PERC cards.
NOTE: Importing secured virtual disks is supported as long as the appropriate local key management (LKM) is supplied or
configured.
NOTE: Virtual disk migration from PERC H740P, H745P, H745, H840 to H345 is not supported.
CAUTION: Do not attempt disk migration during RLM or online capacity expansion (OCE), this causes loss of the
virtual disk.
Virtual disk initialization
PERC 11 series controllers support two types of virtual disk initialization:
● Full initialization
● Fast initialization
Features of PowerEdge RAID Controller 11
19
CAUTION: Initializing virtual disks erases files and file systems while keeping the virtual disk configuration
intact.
Full initialization
Performing a full initialization on a virtual disk overwrites all blocks and destroys any data that previously existed on the virtual
disk. Full initialization of a virtual disk eliminates the need for the virtual disk to undergo a Background Initialization (BGI). Full
initialization can be performed after the virtual disk is created.
You can start a full initialization on a virtual disk by using the Slow Initialize option in the Dell OpenManage storage management
application. For more information on using the HII Configuration Utility to perform a full initialization, see Configure virtual disk
parameters on page 44.
NOTE: If the system reboots during a full initialization, the operation aborts and a BGI begins on the virtual disk.
Fast initialization
A fast initialization on a virtual disk overwrites the first and last 8 MB of the virtual disk, clearing any boot records or partition
information. The operation takes only 2–3 seconds to complete, but it is followed by BGI, which takes a longer time to complete.
To perform a fast initialization using the HII Configuration Utility, see Configure virtual disk parameters on page 44.
NOTE: During full or fast initialization, the host cannot access the virtual disk. As a result, if the host attempts to access
the virtual disk while it is initializing, all I/O sent by the host will fail.
NOTE: When using iDRAC to create a virtual disk, the drive undergoes fast initialization. During this process all I/O requests
to the drive will respond with a sense key of "Not Ready" and the I/O operation will fail. If the operating system attempts
to read from the drive as soon as it discovers the drive, and while the fast initialization is still in process, then the I/O
operation fails and the operating system reports an I/O error.
Reconfiguration of virtual disks
An online virtual disk can be reconfigured in ways that expands its capacity and changes its RAID level.
NOTE: Spanned virtual disks such as RAID 50 and 60 cannot be reconfigured.
NOTE: Reconfiguring virtual disks typically impacts disk performance until the reconfiguration operation is complete.
Online Capacity Expansion (OCE) can be done in two ways:
1. If there is a single virtual disk in a disk group and free space is available, the capacity of a virtual disk can be expanded within
that free space. If multiple virtual disks exist within a common disk group, the capacities of those virtual disks cannot be
expanded.
NOTE:
Online capacity expansion is allowed on a disk group with a single virtual disk that begins at the start of the
physical disk. It is not allowed when there is a free space at the beginning of a disk.
2. Free space is also available when the physical disks of a disk group are replaced by larger disks using the replace member
feature. The capacity of a virtual disk can also be expanded by performing an OCE operation to add more physical disks.
RAID level migration (RLM) refers to changing a virtual disk’s RAID level. Both RLM and OCE can be done simultaneously so
that a virtual disk can simultaneously have its RAID level that is changed and its capacity increased. When an RLM or an OCE
operation is complete, a reboot is not required.
CAUTION: Do not attempt disk migration during RLM or OCE operations. This causes loss of the virtual disk.
NOTE: If an RLM or an OCE operation is in progress, then an automatic drive rebuild or copyback operation will not start
until the operation is complete.
NOTE: If the controller already contains the maximum number of virtual disks, you cannot perform a RAID level migration or
capacity expansion on any virtual disk.
NOTE: The controller changes the write cache policy of all virtual disks to write-through until the RLM or OCE operation is
complete.
20 Features of PowerEdge RAID Controller 11
See the following table for a list of RLM or OCE options: The source RAID level column indicates the virtual disk RAID level
before the RLM or OCE operation and the target RAID level column indicates the RAID level after the RLM or OCE operation.
Table 6. RAID level migration
Source RAID
Level
RAID 0 RAID 0 1 or more 2 or more Yes Increases capacity by adding
RAID 0 RAID 1 1 2 Yes Converts a non-redundant
RAID 0 RAID 5 1 or more 3 or more Yes Adds distributed parity
RAID 0 RAID 6 1 or more 4 or more Yes Adds dual distributed parity
RAID 1 RAID 0 2 2 or more Yes Removes redundancy while
RAID 1 RAID 5 2 3 or more Yes Maintains redundancy while
RAID 1 RAID 6 2 4 or more Yes Adds dual distributed parity
RAID 5 RAID 0 3 or more 2 or more Yes Converts to a non-redundant
Target RAID
Level
Number of
Physical Disks
(Beginning)
Number of
Physical Disks
(End)
Capacity
Expansion
Possible
Description
disks.
virtual disk into a mirrored
virtual disk by adding one disk.
redundancy; at least one disk
needs to be added.
redundancy; at least two disks
need to be added.
increasing capacity.
adding capacity.
redundancy and adds capacity.
virtual disk and reclaims disk
space that is used for
distributed parity data; one
disk can be removed.
RAID 5 RAID 5 3 or more 4 or more Yes Increases capacity by adding
disks.
RAID 5 RAID 6 3 or more 4 or more Yes Adds dual distributed parity
redundancy; at least one disk
needs to be added.
RAID 6 RAID 0 4 or more 2 or more Yes Converts to a non-redundant
virtual disk and reclaims disk
space that is used for
distributed parity data; two
disks can be removed.
RAID 6 RAID 5 4 or more 3 or more Yes Removes one set of parity data
and reclaims disk space used
for it; one disk can be
removed.
RAID 6 RAID 6 4 or more 5 or more Yes Increases capacity by adding
disks.
RAID 10 RAID 10 4 or more 6 or more Yes Increases capacity by adding
disks; an even number of disks
need to be added.
NOTE: The total number of physical disks in a disk group cannot exceed 32. You cannot perform a RAID level migration and
expansion on RAID levels 50 and 60.
Features of PowerEdge RAID Controller 11 21
Background operations
Background initialization
Background initialization (BGI) is an automated process that writes parity or mirror data on newly created virtual disks. BGI does
not run on RAID 0 virtual disks. You can control the BGI rate in the Dell OpenManage storage management application. Any
change to the BGI rate does not take effect until the next BGI is executed.
NOTE:
● You cannot disable BGI permanently. If you cancel BGI, it automatically restarts within five minutes.
● Unlike full or fast initialization of virtual disks, background initialization does not clear data from the physical disks.
● Consistency Check (CC) and BGI typically cause some loss in performance until the operation completes.
Consistency check and BGI perform similar functions in that they both correct parity errors. However, CC reports data
inconsistencies through an event notification, while BGI does not. You can start CC manually, but not BGI.
Consistency checks
Consistency Check (CC) is a background operation that verifies and corrects the mirror or parity data for fault tolerant virtual
disks. It is recommended that you periodically run a consistency check on virtual disks.
You can manually start a CC using the HII Configuration Utility or the Dell OpenManage storage management application. You
can schedule a CC to run on virtual disks using the Dell OpenManage storage management application. To start a CC using the
HII Configuration Utility, see Perform consistency check on page 54.
NOTE: CC or BGI typically causes some loss in performance until the operation completes.
CC and BGI both correct parity errors. However, CC reports data inconsistencies through an event notification, while BGI does
not. You can start CC manually, but not BGI.
Hard drive features
This section lists the following hard drive features supported on PERC 11 cards in detail:
● Self-Encrypting Disks (SED)
● Instant Secure Erase (ISE)
● 4 KB sector disk drives
Self-Encrypting Disks
The PERC 11 series of cards support self-encrypting disks (SED) for protection of data against loss or theft of SEDs. Protection
is achieved by the use of encryption technology on the drives. There is one security key per controller. You can manage the
security key using local key management (LKM) or OpenManage Secure Enterprise Key Manager also referred as Secure
Enterprise Key Manager (SEKM). The security key is used by the controller to lock and unlock access to encryption-capable
physical disks. In order to take advantage of this feature, you must:
● Have SEDs in your system.
● Create a security key.
For more information, see Security key and RAID management section.
NOTE: You cannot enable security on non-optimal virtual disks.
NOTE: PERC 11 supports Trusted Computing Group Enterprise (TCG) Security Subsystem Classes (SSC) SAS or SATA
SED drives and TCG Opal SSC NVMe drives.
22 Features of PowerEdge RAID Controller 11
Instant secure erase
Instant Secure Erase (ISE) drives use the same encryption technology as SED drives but do not allow the encryption key to be
secured. The encryption technology allows the drive to be re-purposed and securely erased using the cryptographic erase
function.
NOTE: ISE drives do not provide protection against theft.
4 KB sector disk drives
PERC 11 controllers support 4 KB sector disk drives, which enables you to efficiently use the storage space.
Before installing Windows on 4 KB sector disk drives, see Windows operating system installation errors.
NOTE: Mixing 512–byte native and 512–byte emulated drives in a virtual disk is allowed, but mixing 512–byte and 4 KB
native drives in a virtual disk is not allowed.
NOTE: 4 K is only supported in UEFI mode and not legacy BIOS.
NOTE: 4 K devices do not appear under the select boot device option. For more information, see Enable boot support.
Fault tolerance
The PERC 11 series supports the following:
● Self-Monitoring and Reporting Technology (SMART)
● Patrol read
● Physical disk failure detection
● Controller cache
● Battery Transparent Learn Cycle
The next sections describe some methods to achieve fault tolerance.
The SMART feature
The SMART feature monitors certain physical aspects of all motors, heads, and physical disk electronics to help detect
predictable physical disk failures. Data on SMART compliant physical disks can be monitored to identify changes in values and
determine whether the values are within threshold limits. Many mechanical and electrical failures display some degradation in
performance before failure.
A SMART failure is also referred to as predicted failure. There are numerous factors that are predicted physical disk failures,
such as a bearing failure, a broken read/write head, and changes in spin-up rate. In addition, there are factors related to read/
write surface failure, such as seek error rate and excessive bad sectors.
NOTE:
For detailed information on SCSI interface specifications, see t10.org and for detailed information on SATA interface
specifications, see t13.org.
Automatic Replace Member with predicted failure
A replace member operation can occur when there is a SMART predictive failure reporting on a physical disk in a virtual disk.
The automatic replace member is initiated when the first SMART error occurs on a physical disk that is part of a virtual disk. The
target disk needs to be a hot spare that qualifies as a rebuild disk. The physical disk with the SMART error is marked as failed
only after the successful completion of the replace member. This prevents the array from reaching degraded state.
If an automatic replace member occurs using a source disk that was originally a hot spare (that was used in a rebuild), and a new
disk is added and set as a target disk for the replace member operation, the hot spare drive will revert to the hot spare state
after the replace member operation successfully completes.
NOTE: To enable automatic replace member, use the Dell storage management application.
Features of PowerEdge RAID Controller 11 23
Patrol Read
The Patrol read feature is designed as a preventative measure to ensure physical disk health and data integrity. Patrol read
scans and resolves potential problems on configured physical disks. The Dell storage management applications can be used to
start patrol read and change its behavior.
The following is an overview of patrol read behavior:
● Patrol read runs on all disks on the controller that are configured as part of a virtual disk, including hot spares.
● Patrol read does not run on physical disks that are not part of a virtual disk or are in Ready state.
● The amount of controller resources dedicated to patrol read operations adjusts based on the number of outstanding disk I/O
operations. For example, if the system is processing a large number of I/O operations, then patrol read uses fewer resources
to allow the I/O to take a higher priority.
● Patrol read does not run on disks that are involved in any of the following operations:
○ Rebuild
○ Replace member
○ Full or background initialization
○ CC
○ RLM or OCE
NOTE: By default, patrol read automatically runs every seven days on configured SAS and SATA hard drives.
For more information about patrol read, see the Dell OpenManage documentation at www.dell.com/openmanagemanuals.
Physical disk failure detection
If a disk fails and it is replaced with a new disk, the controller will automatically start a rebuild on the new disk. See, Configured
slot behavior on page 24. Automatic rebuilds can also occur with hot spares. If you have configured hot spares, the controller
will automatically try to use them to rebuild the degraded virtual disk.
Using persistent hot spare slots
NOTE: The persistent hot spare slot feature is disabled by default.
The PERC 11 series can be configured so that the system backplane or storage enclosure disk slots are dedicated as hot spare
slots. This feature can be enabled using the Dell storage management application.
Once enabled, any slots with hot spares configured automatically become persistent hot spare slots. If a hot spare disk fails or is
removed, a replacement disk that is inserted into the same slot automatically becomes a hot spare with the same properties as
the one it is replacing. If the replacement disk does not match the disk protocol and technology, it does not become a hot spare.
For more information on persistent hot spares, see the Dell OpenManage documentation at www.dell.com/openmanagemanuals.
Configured slot behavior
This feature is similar to persistent hot spare slot behavior. If a redundant VD is configured to the system and if a drive is
replaced, the configured slot will automatically rebuild or copyback on the inserted drive regardless of the data on the drive. This
operation will overwrite the data on the drive.
Table 7. Drive state/operation
Drive state/operation Unconfigured
slot
Slot configured in VD
Insert unconfigured drive into the system Ready Rebuild or copyback start
Insert configured drive into the system Foreign
Insert configured locked drive into the system
(unlockable)
24 Features of PowerEdge RAID Controller 11
Foreign Cryptographic Erase (If configured VD is not
● Rebuild or copyback start
● Original drive data lost
secured)
Table 7. Drive state/operation (continued)
Drive state/operation Unconfigured
slot
Insert locked drive into the system (non-unlockable) Foreign locked Foreign locked
Slot configured in VD
● Rebuild or copyback start
● Original drive data lost
Physical disk hot swapping
Hot swapping is the manual replacement of a disk while the PERC 11 series cards are online and performing their normal
functions. The following requirements must be met before hot swapping a physical disk:
● The system backplane or enclosure must support hot swapping for the PERC 11 series cards.
● The replacement disk must be of the same protocol and disk technology. For example, only a SAS hard drive can replace a
SAS hard drive and only a NVMe drive can replace a NVMe drive.
Using replace member and revertible hot spares
The replace member functionality allows a previously commissioned hot spare to revert to a usable hot spare. When a disk failure
occurs within a virtual disk, an assigned hot spare, dedicated, or global, is commissioned and begins rebuilding until the virtual
disk is optimal. After the failed disk is replaced in the same slot and the rebuild to the hot spare is complete, the controller
automatically starts to copy data from the commissioned hot spare to the newly inserted disk. After the data is copied, the new
disk is a part of the virtual disk and the hot spare is reverted to being a ready hot spare. This allows hot spares to remain in
specific enclosure slots. While the controller is reverting the hot spare, the virtual disk remains optimal. The controller
automatically reverts a hot spare only if the failed disk is replaced with a new disk in the same slot. If the new disk is not placed
in the same slot, a manual replace member operation can be used to revert a previously commissioned hot spare.
NOTE:
A replace member operation typically causes a temporary impact to disk performance. Once the operation
completes, performance returns to normal.
Controller cache
The PERC 11 series of cards contain local DRAM on the controllers. This DRAM can cache I/O operations for Write Back, Read
Ahead virtual disks to improve the performance.
NOTE:
Virtual disks consisting of SSDs may not see a difference in performance using controller cache and may benefit by
Fastpath.
I/O workload that is slow to HDDs, such as random 512 B and 4 kB, may take some time to flush cached data. Cache is flushed
periodically but for configuration changes or system shutdown, the cache is required to be flushed before the operation can be
completed. It can take several minutes to flush cache for some workloads depending on the speed of the HDDs and the amount
of data in the cache.
The following operations require a complete cache flush:
● Configuration changes (add or delete VDs, VD cache setting changes, foreign configuration scan, and import)
● System reboot or shutdown
● Abrupt power loss causing cache preservation
The iDRAC or OpenManage periodically scans for the foreign configurations when the foreign disks are present. This
NOTE:
action degrades the performance. If a foreign disk is present, it is recommended that you import, clear, or remove the
foreign disk to prevent an impact on the performance.
Controller cache preservation
The controller is capable of preserving its cache in the event of a system power outage or improper system shutdown. The
PERC 11 series controller is attached to a battery backup unit (BBU) that provides backup power during system power loss to
preserve the controller's cache data.
Features of PowerEdge RAID Controller 11
25
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