Cisco UCS Servers RAID Guide
Cisco UCS Servers RAID Guide
Updated: February 06, 2018
Americas Headquarters
Cisco Systems, Inc.
170 West Tasman Drive
San Jose, CA 95134-1706
USA
http://www.cisco.com
Tel: 408 526-4000
800 553-NETS (6387)
Fax: 408 527-0883
Text Part Number: OL-26591-01
THE SPECIFICATIONS AND INFORMATION REGARDING THE PRODUCTS IN THIS MANUAL ARE SUBJECT TO CHANGE WITHOUT NOTICE. ALL
STATEMENTS, INFORMATION, AND RECOMMENDATIONS IN THIS MANUAL ARE BELIEVED TO BE ACCURATE BUT ARE PRESENTED WITHOUT
WARRANTY OF ANY KIND, EXPRESS OR IMPLIED. USERS MUST TAKE FULL RESPONSIBILITY FOR THEIR APPLICATION OF ANY PRODUCTS.
THE SOFTWARE LICENSE AND LIMITED WARRANTY FOR THE ACCOMPANYING PRODUCT ARE SET FORTH IN THE INFORMATION PACKET THAT
SHIPPED WITH THE PRODUCT AND ARE INCORPORATED HEREIN BY THIS REFERENCE. IF YOU ARE UNABLE TO LOCATE THE SOFTWARE LICENSE
OR LIMITED WARRANTY, CONTACT YOUR CISCO REPRESENTATIVE FOR A COPY.
The following information is for FCC compliance of Class A devices: This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant
to part 15 of the FCC rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial
environment. This equipment generates, uses, and can radiate radio-frequency energy and, if not installed and used in accordance with the instruction manual, may cause
harmful interference to radio communications. Operation of this equipment in a residential area is likely to cause harmful interference, in which case users will be required
to correct the interference at their own expense.
The following information is for FCC compliance of Class B devices: This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant
to part 15 of the FCC rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates,
uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications.
However, there is no guarantee that interference will not occur in a particular installation. If the equipment causes interference to radio or television reception, which can be
determined by turning the equipment off and on, users are encouraged to try to correct the interference by using one or more of the following measures:
• Reorient or relocate the receiving antenna.
• Increase the separation between the equipment and receiver.
• Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
• Consult the dealer or an experienced radio/TV technician for help.
Modifications to this product not authorized by Cisco could void the FCC approval and negate your authority to operate the product.
The Cisco implementation of TCP header compression is an adaptation of a program developed by the University of California, Berkeley (UCB) as part of UCB’s public
domain version of the UNIX operating system. All rights reserved. Copyright © 1981, Regents of the University of California.
NOTWITHSTANDING ANY OTHER WARRANTY HEREIN, ALL DOCUMENT FILES AND SOFTWARE OF THESE SUPPLIERS ARE PROVIDED “AS IS” WITH
ALL FAULTS. CISCO AND THE ABOVE-NAMED SUPPLIERS DISCLAIM ALL WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING, WITHOUT
LIMITATION, THOSE OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OR ARISING FROM A COURSE OF
DEALING, USAGE, OR TRADE PRACTICE.
IN NO EVENT SHALL CISCO OR ITS SUPPLIERS BE LIABLE FOR ANY INDIRECT, SPECIAL, CONSEQUENTIAL, OR INCIDENTAL DAMAGES, INCLUDING,
WITHOUT LIMITATION, LOST PROFITS OR LOSS OR DAMAGE TO DATA ARISING OUT OF THE USE OR INABILITY TO USE THIS MANUAL, EVEN IF CISCO
OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
Cisco and the Cisco logo are trademarks or registered trademarks of Cisco and/or its affiliates in the U.S. and other countries. To view a list of Cisco trademarks, go to this
URL: www.cisco.com/go/trademarks. Third-party trademarks mentioned are the property of their respective owners. The use of the word partner does not imply a partnership
relationship between Cisco and any other company. (1110R)
Any Internet Protocol (IP) addresses and phone numbers used in this document are not intended to be actual addresses and phone numbers. Any examples, command display
output, network topology diagrams, and other figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses or phone numbers in
illustrative content is unintentional and coincidental.
Cisco UCS Servers RAID Guide
© 2015 Cisco Systems, Inc. All rights reserved.
CONTENTS
CHAPTER
1 RAID Overview 1-1
Information About RAID 1-1
Drive Group 1-1
Virtual Drive 1-1
Disk Striping 1-2
Disk Mirroring (RAID 1 and RAID 10) 1-2
Parity 1-3
Disk Spanning 1-3
Hot Spares 1-4
Global Hot Spare 1-5
Dedicated Hot Spare 1-5
Disk Rebuilds 1-6
Hot Swap 1-6
Drive States 1-7
Virtual Drive States 1-7
RAID Levels 1-8
RAID Levels Summary 1-8
RAID 0 1-9
RAID 1 1-10
RAID 5 1-10
RAID 6 1-12
RAID 00 1-13
RAID 10 1-14
RAID 50 1-15
RAID 60 1-16
Fault Tolerance 1-17
CHAPTER
OL-26591-01
Generic Drive Replacement Procedure 1-18
Removing a Drive from a Server 1-18
Installing a Drive in a Server 1-19
Platform-Specific RAID and Drive Procedures 1-19
2 Using Cisco Integrated Management Controller and Cisco UCS Server Configuration Utility for
RAID Monitoring and Configuring
2-1
Cisco Integrated Management Controller—Viewing Storage Properties 2-1
Cisco UCS Server Configuration Utility—RAID Configuration 2-2
Cisco UCS Servers RAID Guide
iii
Contents
CHAPTER
3 Using Cisco UCS Manager for RAID Configuring and Monitoring 3-1
Cisco UCS Manager Configuration 3-1
Local Disk Configuration Policy 3-1
Guidelines for all Local Disk Configuration Policies 3-2
Guidelines for Local Disk Configuration Policies Configured for RAID 3-3
Creating a Local Disk Configuration Policy 3-4
Changing a Local Disk Configuration Policy 3-6
Deleting a Local Disk Configuration Policy 3-7
Server Disk Drive Monitoring 3-7
Support for Disk Drive Monitoring 3-7
Viewing the Status of a Disk Drive 3-8
Interpreting the Status of a Monitored Disk Drive 3-9
RAID Controllers in UCS Servers 3-10
Determining Which Controller is in Your Server 3-11
RAID Controllers 3-12
Disabling Quiet Boot 3-12
Accessing ROM-Based Controller Utilities 3-13
Documentation About RAID Controllers and LSI Utilities 3-13
Moving a RAID Cluster Using UCS Software Version 1.4(1) 3-13
Moving a RAID Cluster Using UCS Software Version 1.4(2) and Later Releases 3-14
Moving a RAID Cluster Between B200 M3 Servers 3-15
Replacing a Failed Drive in a RAID Cluster 3-16
CHAPTER
iv
4 Configuring the LSI SAS2 Integrated RAID Controller 4-1
Information about LSI Integrated RAID 4-1
Mirrored Volumes 4-3
Operation of Mirrored Volumes 4-3
Mirrored Volume Features 4-6
Mirroring and Mirroring Enhanced Features 4-7
Integrated Striping 4-8
Integrated Striping Features 4-9
Creating Mirrored Volumes 4-10
Launching the LSI SAS2 BIOS Configuration Utility 4-10
Creating Mirrored Volumes 4-11
Creating an Integrated Mirroring Volume 4-11
Creating an Integrated Mirroring Enhanced or Integrated Mirroring and Striping Volume 4-13
Expanding an Integrated Mirroring Volume with OCE 4-14
Managing Hot Spare Disks 4-15
Creating Hot Spare Disks 4-15
Cisco UCS Servers RAID Guide
OL-26591-01
Deleting Hot Spare Disks 4-15
Other Configuration Tasks 4-16
Viewing Volume Properties 4-16
Running a Consistency Check 4-16
Activating an Array 4-17
Deleting an Array 4-17
Locating Disk Drives in a Volume 4-18
Choosing a Boot Disk 4-18
Creating Integrated Striping Volumes 4-19
Other Configuration Tasks 4-21
Viewing Volume Properties 4-21
Activating an Array 4-21
Deleting an Array 4-21
Locating Disk Drives in a Volume 4-22
Choosing a Boot Disk 4-23
Contents
CHAPTER
Determining Which Controller is in Your Server 4-23
Disabling Quiet Boot for CIMC Firmware Earlier than Release 1.2(1) 4-24
Launching Option ROM-Based Controller Utilities 4-24
Restoring RAID Configuration After Replacing a RAID Controller 4-25
5 LSI MegaRAID SAS Controller Tasks 5-1
LSI MegaRAID Controller Management Utilities 5-1
LSI WebBIOS Configuration Utility 5-1
MegaRAID Command Tool 5-2
MegaRAID Storage Manager 5-2
LSI WebBIOS CU 5-2
Starting the WebBIOS CU 5-2
WebBIOS CU Main Menu Window Options 5-3
Toolbar 5-4
Menu Options 5-4
Configuring RAID Drive Groups and Virtual Drives 5-5
Choosing the Configuration with the Configuration Wizard 5-5
Using Automatic Configuration 5-5
Using Manual Configuration 5-6
Viewing and Changing Device Properties 5-11
Viewing Controller Properties 5-11
Viewing Virtual Drive Properties, Policies, and Operations 5-13
Viewing Physical Drive Properties and Operations 5-14
Viewing and Changing Battery Backup Unit Information 5-15
OL-26591-01
Cisco UCS Servers RAID Guide
v
Contents
Managing RAID 5-16
Expanding a Virtual Drive 5-16
Monitoring Array Health 5-16
Recovery 5-17
Deleting a Virtual Drive 5-18
Migrating an Array to a New Server 5-18
Foreign Configurations in Cable Pull and Drive Removal Scenarios 5-19
Importing Foreign Configurations from Integrated RAID to MegaRAID 5-20
Troubleshooting Information 5-20
Migrating the RAID Level of a Virtual Drive 5-20
Determining Which Controller is in Your Server 5-22
Disabling Quiet Boot for CIMC Firmware Earlier than Release 1.2(1) 5-22
Launching an Option ROM-Based Controller Utility 5-22
LSI MegaRAID Card Beep Codes 5-23
Restoring the RAID Configuration After Replacing a RAID Controller 5-23
CHAPTER
Limitation on Importing Foreign Configuration To a Virtual Disk That is Under Construction 5-25
Limitation 5-25
Design 5-25
Prerequisites For Reconstruction to Start 5-26
6 Configuring the Embedded ICH10R SATA Controller 6-1
Enabling the Integrated Intel ICH10R RAID Controller in the BIOS 6-1
Launching the LSI Software RAID Setup Utility 6-1
Configuring the Onboard Intel ICH10R RAID Controller 6-2
Creating a New RAID Configuration 6-3
Viewing or Changing a RAID Configuration 6-4
vi
Cisco UCS Servers RAID Guide
OL-26591-01
RAID Overview
This chapter describes RAID (Redundant Array of Independent Disks), RAID functions and benefits,
RAID components, RAID levels, and configuration strategies.
This chapter contains the following sections:
• Information About RAID, page 1-1
• RAID Levels, page 1-8
• Generic Drive Replacement Procedure, page 1-18
• Platform-Specific RAID and Drive Procedures, page 1-19
Information About RAID
RAID is an array, or group, of multiple independent physical drives that provide high performance and
fault tolerance. A RAID drive group improves input/output (I/O) performance and reliability. The RAID
drive group appears to the host computer as a single storage unit or as multiple virtual units. I/O is
expedited because several drives can be accessed simultaneously.
RAID drive groups improve data storage reliability and fault tolerance compared to single-drive storage
systems. Data loss resulting from a drive failure can be prevented by reconstructing missing data from
the remaining drives. RAID improves I/O performance and increases storage subsystem reliability.
RAID levels describe a system for ensuring the availability and redundancy of data stored on large disk
subsystems. See RAID Levels, page 1-8 for detailed information about RAID levels. The RAID
drive-group components and RAID levels are described in the following sections.
CHA P T ER
1
Drive Group
Virtual Drive
OL-26591-01
A drive group is a group of physical drives. These drives are managed in partitions known as virtual
drives.
A virtual drive is a partition in a drive group that is made up of contiguous data segments on the drives.
A virtual drive can consist of an entire drive group, more than one entire drive group, a part of a drive
group, parts of more than one drive group, or a combination of any two of these conditions.
Cisco UCS Servers RAID Guide
1-1
Information About RAID
Segment 1
Segment 5
Segment 9
Segment 2
Segment 6
Segment 10
Segment 3
Segment 7
Segment 11
Segment 4
Segment 8
Segment 12
332084
Disk Striping
Chapter 1 RAID Overview
Disk striping (used in RAID level 0) allows you to write data across multiple drives instead of only one
drive. Disk striping involves partitioning each drive storage space into stripes that can vary in size from
8 KB to 1024 KB. These stripes are interleaved in a repeated sequential manner. The combined storage
space is composed of stripes from each drive. We recommend that you keep stripe sizes the same across
RAID drive groups.
For example, in a four-disk system using only disk striping, segment 1 is written to disk 1, segment 2 is
written to disk 2, and so on (see Figure 1-1). Disk striping enhances performance because multiple drives
are accessed simultaneously, but disk striping does not provide data redundancy
Figure 1-1 Example of Disk Striping (RAID 0)
Stripe width is the number of drives involved in a drive group where striping is implemented. For
example, a four-disk drive group with disk striping has a stripe width of four.
The stripe size is the length of the interleaved data segments that the RAID controller writes across
multiple drives, not including parity drives. For example, consider a stripe that contains 64 KB of disk
space and has 16 KB of data residing on each disk in the stripe. In this case, the stripe size is 64 KB and
the strip size is 16 KB.
The strip size is the portion of a stripe that resides on a single drive.
Disk Mirroring (RAID 1 and RAID 10)
With disk mirroring (used in RAID 1 and RAID 10), data written to one drive is simultaneously written
to another drive. The primary advantage of disk mirroring is that it provides 100 percent data
redundancy. Because the contents of the disk are completely written to a second disk, data is not lost if
one disk fails. In addition, both drives contain the same data at all times, so either disk can act as the
operational disk. If one disk fails, the contents of the other disk can be used to run the system and
reconstruct the failed disk.
Disk mirroring provides 100 percent redundancy but is expensive because each drive in the system must
be duplicated (see Figure 1-2).
1-2
Cisco UCS Servers RAID Guide
OL-26591-01
Chapter 1 RAID Overview
Segment 1
Segment 2
Segment 3
Segment 1 Duplicated
Segment 2 Duplicated
Segment 3 Duplicated
Segment 4 Segment 4 Duplicated
Parity
Information About RAID
Figure 1-2 Example of Disk Mirroring (RAID 1)
Parity generates a set of redundancy data from two or more parent data sets. The redundancy data can
be used to reconstruct one of the parent data sets in the event of a drive failure. Parity data does not fully
duplicate the parent data sets, but parity generation can slow the write process. In RAID, this method is
applied to entire drives or stripes across all of the drives in a drive group. There are two types of parity:
• Dedicated parity—The parity data on two or more drives is stored on an additional disk.
Note Parity is distributed across all drives in the drive group.
Disk Spanning
• Distributed parity—The parity data is distributed across more than one drive in the system.
RAID 5 combines distributed parity with disk striping (see Figure 1-3). If a single drive fails, it can be
rebuilt from the parity and the data on the remaining drives. RAID 5 uses parity to provide redundancy
for one drive failure without duplicating the contents of entire drives. RAID 6 uses distributed parity and
disk striping also but adds a second set of parity data so that it can survive up to two drive failures.
Figure 1-3 Example of Distributed Parity (RAID 5)
Segment 1
Segment 7
Segment 13
Segment 19
Segment 25
Parity (26–30)
Segment 2
Segment 8
Segment 14
Segment 20
Parity (21–25)
Segment 26
Segment 3
Segment 9
Segment 15
Parity (16–20)
Segment 21
Segment 4
Segment 10
Parity (11–15)
Segment 16
Segment 22
Segment 28
Segment 5
Parity (6–10)
Segment 11
Segment 17
Segment 23
92 tnemgeS72 tnemgeS
Parity (1–5)
Segment 6
Segment 12
Segment 18
Segment 24
Segment 30
332086
Disk spanning allows multiple drives to function like one big drive. Spanning overcomes lack of disk
space and simplifies storage management by combining existing resources or adding relatively
inexpensive resources. For example, four 20-GB drives can be combined to appear to the operating
system as a single 80-GB drive.
OL-26591-01
Cisco UCS Servers RAID Guide
1-3
Information About RAID
60 GB 60 GB
Can be accessed as
one 120-GB drive
60 GB 60 GB
Can be accessed as
one 120-GB drive
332087
Note Make sure that the spans are in different backplanes, so that if one span fails, you do not lose the whole
Chapter 1 RAID Overview
Spanning alone does not provide reliability or performance enhancements. Spanned virtual drives must
have the same stripe size and must be contiguous. In Figure 1-4, RAID 1 drive groups are turned into a
RAID 10 drive group.
drive group.
Figure 1-4 Example of Disk Spanning
Spanning two contiguous RAID 0 virtual drives does not produce a new RAID level or add fault
tolerance. It does increase the capacity of the virtual drive and improves performance by doubling the
number of physical disks.
Table 1 -1 describes how to configure RAID 00, RAID 10, RAID 50, and RAID 60 by spanning. The
virtual drives must have the same stripe size and the maximum number of spans is eight. The full drive
capacity is used when you span virtual drives; you cannot specify a smaller drive capacity.
Table 1-1 Spanning for RAID 00, RAID 10, RAID 50, and RAID 60
RAID
Level Description
00 Configure RAID 00 by spanning two contiguous RAID 0 virtual drives, up to the maximum
number of supported devices for the controller.
10 Configure RAID 10 by spanning two contiguous RAID 1 virtual drives, up to the maximum
number of supported devices for the controller.
RAID 10 supports a maximum of eight spans. You must use an even number of drives in each
RAID virtual drive in the span.
The RAID 1 virtual drives must have the same stripe size.
50 Configure RAID 50 by spanning two contiguous RAID 5 virtual drives.
The RAID 5 virtual drives must have the same stripe size.
60 Configure RAID 60 by spanning two contiguous RAID 6 virtual drives.
The RAID 6 virtual drives must have the same stripe size.
Hot Spares
1-4
Cisco UCS Servers RAID Guide
A hot spare is an extra, unused drive that is part of the disk subsystem. It is usually in standby mode,
ready for service if a drive fails. If a drive used in a RAID virtual drive fails, a hot spare automatically
takes its place and the data on the failed drive is rebuilt on the hot spare. Hot spares can be used for RAID
levels 1, 5, 6, 10, 50, and 60.
OL-26591-01
Chapter 1 RAID Overview
Note When running RAID 0 and RAID 5 virtual drives on the same set of drives (a sliced configuration), a
Information About RAID
Hot spares permit you to replace failed drives without system shutdown or user intervention. MegaRAID
SAS RAID controllers can implement automatic and transparent rebuilds of failed drives using hot spare
drives, providing a high degree of fault tolerance and zero downtime.
rebuild to a hot spare cannot occur after a drive failure until the RAID 0 virtual drive is deleted.
The LSI RAID management software allows you to specify drives as hot spares. When a hot spare is
needed, the RAID controller assigns the hot spare that has a capacity closest to and at least as great as
that of the failed drive to take the place of the failed drive. The failed drive is removed from the virtual
drive and marked ready awaiting removal once the rebuild to a hot spare begins. You can make hot spares
of the drives that are not in a RAID virtual drive.
You can use the RAID management software to designate the hot spare to have enclosure affinity, which
means that if drive failures are present on a split backplane configuration, the hot spare is used first on
the backplane side that it resides in.
If the hot spare is designated as having enclosure affinity, it attempts to rebuild any failed drives on the
backplane that it resides in before rebuilding any other drives on other backplanes.
Note If a rebuild to a hot spare fails for any reason, the hot spare drive is marked as failed. If the source drive
fails, both the source drive and the hot spare drive is marked as failed.
There are two types of hot spares:
• Global hot spare
• Dedicated hot spare
Global Hot Spare
A global hot spare drive can be used to replace any failed drive in a redundant drive group as long as its
capacity is equal to or larger than the capacity of the failed drive. A global hot spare defined on any
channel should be available to replace a failed drive on both channels.
Dedicated Hot Spare
A dedicated hot spare can be used to replace a failed drive only in a chosen drive group. One or more
drives can be designated as a member of a spare drive pool. The most suitable drive from the pool is
chosen for failover. A dedicated hot spare is used before one from the global hot spare pool.
Hot spare drives can be located on any RAID channel. Standby hot spares (not being used in RAID drive
group) are polled every 60 seconds at a minimum, and their status is made available in the drive group
management software. RAID controllers offer the ability to rebuild with a disk that is in a system, but
not initially set to be a hot spare.
When using hot spares, observe the following guidelines:
OL-26591-01
• Hot spares are used only in drive groups with redundancy, which includes RAID levels 1, 5, 6, 10,
50, and 60.
• A hot spare connected to a specific RAID controller can be used to rebuild a drive that is connected
to the same controller only.
Cisco UCS Servers RAID Guide
1-5
Information About RAID
Disk Rebuilds
Chapter 1 RAID Overview
• You must assign the hot spare to one or more drives through the controller BIOS or use drive group
management software to place it in the hot spare pool.
• A hot spare must have free space equal to or greater than the drive it replaces. For example, to
replace an 18-GB drive, the hot spare must be 18 GB or larger.
When a drive in a RAID drive group fails, you can rebuild the drive by recreating the data that was stored
on the drive before it failed. The RAID controller recreates the data using the data stored on the other
drives in the drive group. Rebuilding can be done only in drive groups with data redundancy, which
includes RAID 1, 5, 6, 10, 50, and 60 drive groups.
The RAID controller uses hot spares to rebuild failed drives automatically and transparently, at
user-defined rebuild rates. If a hot spare is available, the rebuild can start automatically when a drive
fails. If a hot spare is not available, the failed drive must be replaced with a new drive so that the data on
the failed drive can be rebuilt.
The failed drive is removed from the virtual drive and marked ready awaiting removal when the rebuild
to a hot spare begins. If the system goes down during a rebuild, the RAID controller automatically
restarts the rebuild after the system reboots.
Hot Swap
Note When the rebuild to a hot spare begins, the failed drive is often removed from the virtual drive before
management applications detect the failed drive. When this situation occurs, the events logs show the
drive rebuilding to the hot spare without showing the failed drive. The formerly failed drive is marked
as ready after a rebuild begins to a hot spare.
Note If a source drive fails during a rebuild to a hot spare, the rebuild fails, and the failed source drive is
marked as offline. In addition, the rebuilding hot spare drive is changed back to a hot spare. After a
rebuild fails because of a source drive failure, the dedicated hot spare is still dedicated and assigned to
the correct drive group, and the global hot spare is still global.
An automatic drive rebuild does not start if you replace a drive during a RAID-level migration. The
rebuild must be started manually after the expansion or migration procedure is complete. (RAID-level
migration changes a virtual drive from one RAID level to another.)
A hot swap is the manual replacement of a defective drive unit while the computer is still running
(performing its normal functions). When a new drive is installed, a rebuild occurs automatically if one
of the following happens:
• The newly inserted drive is the same capacity as or larger than the failed drive.
• It is placed in the same drive bay as the failed drive it is replacing.
The RAID controller can be configured to detect the new drives and rebuild the contents of the drive
automatically. The backplane and enclosure must support hot swap for the functionality to work.
1-6
Cisco UCS Servers RAID Guide
OL-26591-01
Chapter 1 RAID Overview
Drive States
Information About RAID
A drive state is a property that indicates the status of the drive. Table 1-2 describes the drive states.
Table 1-2 Drive States
State Description
Online A drive that can be accessed by the RAID controller and is part of the virtual drive.
Unconfigured
Good
Hot Spare A drive that is powered up and ready for use as a spare in case an online drive fails.
Failed A drive that was originally configured as Online or Hot Spare but on which the
Rebuild A drive to which data is being written to restore full redundancy for a virtual drive.
Unconfigured
Bad
Missing A drive that was Online but which has been removed from its location.
Offline A drive that is part of a virtual drive but which has invalid data as far as the RAID
A drive that is functioning normally but is not configured as a part of a virtual drive
or as a hot spare.
firmware detects an unrecoverable error.
A drive on which the firmware detects an unrecoverable error; the drive was
Unconfigured Good or the drive could not be initialized.
configuration is concerned.
When a virtual drive with cached data goes offline, the cache for the virtual drive is
discarded. Because the virtual drive is offline, the cache cannot be saved.
Virtual Drive States
A virtual drive state is a property indicating the status of the virtual drive. Tabl e 1-3 describes the virtual
drive states.
Table 1-3 Virtual Drive States
State Description
Optimal The virtual drive operating condition is good. All configured drives are online.
Degraded The virtual drive operating condition is not optimal. One of the configured drives has
Partial
Degraded
Failed The virtual drive has failed.
Offline The virtual drive is not available to the RAID controller.
failed or is offline.
The operating condition in a RAID 6 virtual drive is not optimal. One of the
configured drives has failed or is offline. RAID 6 can tolerate up to two drive failures.
OL-26591-01
Cisco UCS Servers RAID Guide
1-7
RAID Levels
RAID Levels
The MegaRAID controller supports RAID levels 0, 00, 1, 5, 6, 10, 50, and 60. It also supports
independent drives (configured as RAID 0 and RAID 00.) The supported RAID levels are summarized
in the following section.
RAID Levels Summary
• RAID 0 uses striping to provide high data throughput, especially for large files in an environment
that does not require fault tolerance.
• RAID 1 uses mirroring so that data written to one drive is simultaneously written to another drive
which is good for small databases or other applications that require small capacity, but complete data
redundancy.
• RAID 5 uses disk striping and parity data across all drives (distributed parity) to provide high data
throughput, especially for small random access.
• RAID 6 uses distributed parity, with two independent parity blocks per stripe, and disk striping. A
RAID 6 virtual drive can survive the loss of two drives without losing data. A RAID 6 drive group,
which requires a minimum of three drives, is similar to a RAID 5 drive group. Blocks of data and
parity information are written across all drives. The parity information is used to recover the data if
one or two drives fail in the drive group.
• A RAID 00 drive group is a spanned drive group that creates a striped set from a series of RAID 0
drive groups.
• RAID 10, a combination of RAID 0 and RAID 1, consists of striped data across mirrored spans. A
RAID 10 drive group is a spanned drive group that creates a striped set from a series of mirrored
drives. RAID 10 allows a maximum of eight spans. You must use an even number of drives in each
RAID virtual drive in the span. The RAID 1 virtual drives must have the same stripe size. RAID 10
provides high data throughput and complete data redundancy but uses a larger number of spans.
Chapter 1 RAID Overview
1-8
• RAID 50, a combination of RAID 0 and RAID 5, uses distributed parity and disk striping. A
RAID 50 drive group is a spanned drive group in which data is striped across multiple RAID 5 drive
groups. RAID 50 works best with data that requires high reliability, high request rates, high data
transfers, and medium-to-large capacity.
Note You cannot have virtual drives of different RAID levels, such as RAID 0 and RAID 5, in the same drive
group. For example, if an existing RAID 5 virtual drive is created out of partial space in an array, the
next virtual drive in the array has to be RAID 5 only.
• RAID 60, a combination of RAID 0 and RAID 6, uses distributed parity, with two independent
parity blocks per stripe in each RAID set, and disk striping. A RAID 60 virtual drive can survive the
loss of two drives in each of the RAID 6 sets without losing data. It works best with data that
requires high reliability, high request rates, high data transfers, and medium-to-large capacity.
Cisco UCS Servers RAID Guide
OL-26591-01
Chapter 1 RAID Overview
RAID 0
Note RAID level 0 is not fault tolerant. If a drive in a RAID 0 drive group fails, the whole virtual drive (all
RAID Levels
RAID 0 provides disk striping across all drives in the RAID drive group. RAID 0 does not provide any
data redundancy but does offer the best performance of any RAID level. RAID 0 breaks up data into
smaller segments and stripes the data segments across each drive in the drive group. The size of each
data segment is determined by the stripe size. RAID 0 offers high bandwidth.
drives associated with the virtual drive) will fail.
By breaking up a large file into smaller segments, the RAID controller can use both SAS drives and
SATA drives to read or write the file faster. RAID 0 involves no parity calculations to complicate the
write operation, which makes RAID 0 ideal for applications that require high bandwidth, but do not
require fault tolerance. Tab le 1-4 provides an overview of RAID 0. Figure 1-5 shows an example of a
RAID 0 drive group advantage.
Table 1-4 RAID 0 Overview
Feature Description
Uses Provides high data throughput, especially for large files. Any environment that does
not require fault tolerance.
Benefits Provides increased data throughput for large files.
No capacity loss penalty for parity.
Limitations Does not provide fault tolerance or high bandwidth.
All data is lost if any drive fails.
Drives 1 to 32.
Figure 1-5 RAID 0 Drive Group Example
Segment 1
Segment 3
Segment 5
Segment 7 Segment 8
Segment 2
Segment 4
Segment 6
332088
OL-26591-01
Cisco UCS Servers RAID Guide
1-9
RAID Levels
RAID 1
Chapter 1 RAID Overview
In RAID 1, the RAID controller duplicates all data from one drive to a second drive in the drive group.
RAID 1 supports an even number of drives from 2 to 32 in a single span. RAID 1 provides complete data
redundancy but at the cost of doubling the required data storage capacity. Tab le 1- 5 provides an overview
of RAID 1. Figure 1-6 shows an example of a RAID 1 drive group.
Table 1-5 RAID 1 Overview
Feature Description
Uses Use RAID 1 for small databases or any other environment that requires fault
tolerance, but small capacity.
Benefits Provides complete data redundancy. RAID 1 is ideal for any application that requires
fault tolerance and minimal capacity.
Limitations Requires twice as many drives. Performance is impaired during drive rebuilds.
Drives 2 to 32 (must be an even number of drives).
RAID 5
Figure 1-6 RAID 1 Drive Group Example
Segment 1
Segment 5
...
RAID1
Segment 1
Duplicate
Segment 5
Duplicate
Segment 2
Segment 6
...
RAID1
Segment 2
Duplicate
Segment 6
Duplicate
Segment 3
Segment 7
...
RAID1
Segment 3
Duplicate
Segment 7
Duplicate
Segment 4
Segment 8
...
Segment 4
Duplicate
Segment 8
Duplicate
RAID1
332089
RAID 5 includes disk striping at the block level and parity. Parity is the property of the data of being odd
or even, and parity checking is used to detect errors in the data. In RAID 5, the parity information is
written to all drives. RAID 5 is best suited for networks that perform a lot of small input/output (I/O)
transactions simultaneously. RAID 5 provides data redundancy, high read rates, and good performance
in most environments. It also provides redundancy with the lowest loss of capacity.
In addition, RAID 5 is good for any application that has high read request rates but has low write request
rates.
RAID 5 addresses the congestion issue for random I/O operations. Because each drive contains both data
and parity, numerous writes can take place concurrently.
Table 1 -6 provides an overview of RAID 5. Figure 1-7 shows an example of a RAID 5 drive group.
1-10
Cisco UCS Servers RAID Guide
OL-26591-01
Chapter 1 RAID Overview
Segment 1
Segment 7
Segment 2
Segment 8
Segment 3
Segment 9
Segment 4
Segment 10
Segment 5
Parity (6–10)
Parity (11–15)
Parity (1–5)
Segment 6
Segment 12
Segment 15
Segment 11
Segment 14
Segment 13
Segment 19
Segment 25
Segment 20
Segment 23
Segment 18
Segment 21
Segment 16
Segment 22
Segment 17
Parity (21–25)
Parity (26–30)
Parity (16–20)
Segment 24
Segment 30
92 tnemgeS72 tnemgeS
Segment 26
Segment 28
332090
RAID Levels
Table 1-6 RAID 5 Overview
Features Description
Uses Provides high data throughput, especially for large files. Use RAID 5 for transaction
processing applications because each drive can read and write independently. If a
drive fails, the RAID controller uses the parity drive to recreate all missing
information. Use also for office automation and online customer service that requires
fault tolerance. Use for any application that has high read request rates but low write
request rates.
Benefits Provides data redundancy, high read rates, and good performance in most
environments. RAID 5 provides redundancy with the lowest loss of capacity.
Limitations Not well-suited to tasks that require a large number of writes. RAID 5 has problems
if no cache is used (clustering). The drive’s performance is reduced if a drive is being
rebuilt. Environments with few processes do not perform as well because the RAID
overhead is not offset by the performance gains in handling simultaneous processes.
Drives 3 to 32.
Note Parity is distributed across all drives in the drive group.
Figure 1-7 RAID 5 Drive Group Example
OL-26591-01
Cisco UCS Servers RAID Guide
1-11
RAID Levels
RAID 6
Chapter 1 RAID Overview
RAID 6 is similar to RAID 5 (disk striping and distributed parity), except that instead of one parity block
per stripe, there are two. With two independent parity blocks, RAID 6 can survive the loss of two drives
in a virtual drive without losing data. RAID 6 provides a high level of data protection through the use of
a second parity block in each stripe. Use RAID 6 for data that requires a very high level of protection
from loss.
RAID 6 is best suited for networks that perform a lot of small input/output (I/O) transactions
simultaneously. It provides data redundancy, high read rates, and good performance in most
environments.
In the case of a failure of one drive or two drives in a virtual drive, the RAID controller uses the parity
blocks to recreate all of the missing information. If two drives in a RAID 6 virtual drive fail, two drive
rebuilds are required, one for each drive. These rebuilds do not occur at the same time. The controller
rebuilds one failed drive and then the other failed drive.
Table 1 -7 provides an overview of a RAID 6 drive group. Figure 1-8 shows a RAID 6 data layout. The
second set of parity drives are denoted by Q. The P drives follow the RAID 5 parity scheme.
Table 1-7 RAID 6 Overview
Features Description
Uses Use for office automation and online customer service that requires fault tolerance.
Use for any application that has high read request rates but low write request rates.
Benefits Provides data redundancy, high read rates, and good performance in most
environments, can survive the loss of two drives or the loss of a drive while another
drive is being rebuilt, and provides the highest level of protection against drive
failures of all of the RAID levels. The read performance is similar to that of RAID 5.
Limitations Not well-suited to tasks that require a large number of writes. A RAID 6 virtual drive
has to generate two sets of parity data for each write operation, which results in a
significant decrease in performance during writes. The drive performance is reduced
during a drive rebuild. Environments with few processes do not perform as well,
because the RAID overhead is not offset by the performance gains in handling
simultaneous processes. RAID 6 costs more because of the extra capacity required
by using two parity blocks per stripe.
Drives 3 to 32.
Note Parity is distributed across all drives in the drive group.
1-12
Cisco UCS Servers RAID Guide
OL-26591-01
Chapter 1 RAID Overview
Segment 1
Segment 6
Segment 2
Segment 7
Segment 3
Segment 8
Segment 4
Parity (P5–P8)
Parity (P1–P4)
Parity (Q5–Q8)
Parity (Q9–Q12)
Parity (Q1–Q4)
Segment 5
Segment 10
Parity (P9–P12)
Segment 9
Segment 12
Segment 11
Segment 16
Parity (P17–P20)
Parity (P13–P16)
Segment 19
Segment 15
Segment 17
Segment 13
Segment 18
Segment 14
Parity (Q17–Q20)
Parity (Q13–Q16)
Segment 20
332094
RAID 00
RAID Levels
Figure 1-8 RAID 6 Drive Group Example
A RAID 00 drive group is a spanned drive group that creates a striped set from a series of RAID 0 drive
groups. RAID 00 does not provide any data redundancy, but along with RAID 0, RAID 00 offers the best
performance of any RAID level. RAID 00 breaks up data into smaller segments and stripes the data
segments across each drive in the drive groups. The size of each data segment is determined by the stripe
size. RAID 00 offers high bandwidth.
Note RAID level 00 is not fault tolerant. If a drive in a RAID 0 drive group fails, the whole virtual drive (all
drives associated with the virtual drive) fails.
By breaking up a large file into smaller segments, the RAID controller can use both SAS drives and
SATA drives to read or write the file faster. RAID 00 involves no parity calculations to complicate the
write operation, which makes RAID 00 ideal for applications that require high bandwidth but do not
require fault tolerance. Tab le 1-8 provides an overview of RAID 00. Figure 1-9 shows an example of a
RAID 00 drive group.
Table 1-8 RAID 00 Overview
Features Description
Uses Provides high data throughput, especially for large files. Use RAID 00 in any
environment that does not require fault tolerance.
Benefits Provides increased data throughput for large files. RAID 00 has no capacity loss
penalty for parity.
Limitations Does not provide fault tolerance or high bandwidth. All data is lost if any drive fails.
Drives Two to the maximum number of drives that are supported by the controller.
OL-26591-01
Cisco UCS Servers RAID Guide
1-13
RAID Levels
Segment 1
Segment 2Segment
3
Segment 6
Segment
8
Segment
5
Segment 7
Segment
9
Segment
11
Segment
13
Segment 15
Segment
10
Segment
12
Segment
14
Segment
16
Segment
4
...
...
...
...
RAID
0
RAID
0
RAID
0
RAID
0
RAID
00
RAID 0
Segment
17
Segment
18
Segment
19
Segment 20Segment
21
Segment
22
Segment
23
Segment
24
RAID 10
Chapter 1 RAID Overview
Figure 1-9 RAID 00 Drive Group Example Using Two Drives
RAID 10 is a combination of RAID 0 and RAID 1 and consists of stripes across mirrored drives.
RAID 10 breaks up data into smaller blocks and mirrors the blocks of data to each RAID 1 drive group.
The first RAID 1 drive in each drive group then duplicates its data to the second drive. The size of each
block is determined by the stripe size parameter, which is set during the creation of the RAID set. The
RAID 1 virtual drives must have the same stripe size.
1-14
Spanning is used because one virtual drive is defined across more than one drive group. Virtual drives
defined across multiple RAID 1 level drive groups are referred to as RAID level 10, (1+0). Data is striped
across drive groups to increase performance by enabling access to multiple drive groups simultaneously.
Each spanned RAID 10 virtual drive can tolerate multiple drive failures, as long as each failure is in a
separate drive group. If there are drive failures, less than the total drive capacity is available.
Configure RAID 10 by spanning two contiguous RAID 1 virtual drives, up to the maximum number of
supported devices for the controller. RAID 10 supports a maximum of eight spans with a maximum of
32 drives per span. You must use an even number of drives in each RAID 10 virtual drive in the span.
Note Other factors, such as the type of controller, can restrict the number of drives supported by RAID 10
virtual drives.
Table 1 -9 provides an overview of RAID 10. In Figure 1-10, virtual drive 0 is created by distributing
data across four RAID 1 drive groups (drive groups 0 through 3).
Table 1-9 RAID 10 Overview
Benefits Description
Uses Appropriate when used with data storage that needs 100 percent redundancy of
mirrored drive groups and that also needs the enhanced I/O performance of RAID 0
(striped drive groups.) RAID 10 works well for medium-sized databases or any
environment that requires a higher degree of fault tolerance and moderate to medium
capacity.
Benefits Provides both high data transfer rates and complete data redundancy.
Limitations Requires twice as many drives as all other RAID levels except RAID 1.
Drives Two to 8 equal spans of RAID 1 drive groups containing 2 to 32 drives each (limited
by the maximum number of devices supported by the controller). You must use an
Cisco UCS Servers RAID Guide
even number of drive spans.
OL-26591-01
Chapter 1 RAID Overview
RAID Levels
Figure 1-10 RAID 10 Virtual Drive Example
RAID 50
RAID 10
Segment 1
Segment 5
...
RAID1
Segment 1
Duplicate
Segment 5
Duplicate
Segment 2
Segment 6
...
RAID1
Segment 2
Duplicate
Segment 6
Duplicate
RAID 0
Segment 3
Segment 7
...
RAID1
Segment 3
Duplicate
Segment 7
Duplicate
Segment 4
Segment 8
...
Segment 4
Duplicate
Segment 8
Duplicate
RAID1
RAID 50 provides the features of both RAID 0 and RAID 5. RAID 50 includes both parity and disk
striping across multiple drive groups. RAID 50 is best implemented on two RAID 5 drive groups with
data striped across both drive groups.
RAID 50 breaks up data into smaller blocks and stripes the blocks of data to each RAID 5 disk set.
RAID 5 breaks up data into smaller blocks, calculates parity, and writes the blocks of data and parity to
each drive in the drive group. The size of each block is determined by the stripe size parameter, which
is set during the creation of the RAID set.
RAID level 50 can support up to eight spans and tolerate up to eight drive failures though less than total
drive capacity is available. Though multiple drive failures can be tolerated, only one drive failure can be
tolerated in each RAID 5 level drive group.
Table 1 -10 provides an overview of RAID 50. In Figure 1-11, virtual drive 0 is created by distributing
data across two RAID 5 drive groups.
332143
Table 1-10 RAID 50 Overview
Features Description
Uses Appropriate when used with data that requires high reliability, high request rates,
high data transfer, and medium to large capacity.
Benefits Provides high data throughput, data redundancy, and very good performance.
Limitations Requires 2 to 8 times as many parity drives as RAID 5.
Drives Two to 8 equal spans of RAID 5 drive groups containing 3 to 32 drives each (limited
by the maximum number of devices supported by the controller.)
OL-26591-01
Cisco UCS Servers RAID Guide
1-15
RAID Levels
Segment 1
Segment 2
Segment 5
Segment 6
RAID 0
RAID 50
(Segment 1,2)
Segment 3
Segment 4
Segment 8
Segment 7
Segment 9
Segment 10
Segment 11
Segment 12
(Segment 5,6)
(Segment 9,10)
(Segment 11,12)
(Segment 7,8)
(Segment 3,4)
RAID 5 RAID 5
332097
RAID 60
Chapter 1 RAID Overview
Figure 1-11 RAID 50 Virtual Drive Example
RAID 60 provides the features of both RAID 0 and RAID 6 and includes both parity and disk striping
across multiple drive groups. RAID 6 supports two independent parity blocks per stripe. A RAID 60
virtual drive can survive the loss of two drives in each of the RAID 6 sets without losing data. RAID 60
is best implemented on two RAID 6 drive groups with data striped across both drive groups.
RAID 60 breaks up data into smaller blocks and stripes the blocks of data to each RAID 6 disk set.
RAID 6 breaks up data into smaller blocks, calculates parity, and writes the blocks of data and parity to
each drive in the drive group. The size of each block is determined by the stripe size parameter, which
is set during the creation of the RAID set.
RAID 60 can support up to 8 spans and tolerate up to 16 drive failures though less than total drive
capacity is available. Two drive failures can be tolerated in each RAID 6 level drive group.
Table 1 -11 provides an overview of RAID 60. Figure 1-12 shows a RAID 6 data layout. The second set
of parity drives are denoted by Q. The P drives follow the RAID 5 parity scheme.
Table 1-11 RAID 60 Overview
Features Description
Uses Provides a high level of data protection through the use of a second parity block in
each stripe. Use RAID 60 for data that requires a very high level of protection from
loss.
In the case of a failure of one drive or two drives in a RAID set in a virtual drive, the
RAID controller uses the parity blocks to recreate all of the missing information. If
two drives in a RAID 6 set in a RAID 60 virtual drive fail, two drive rebuilds are
required, one for each drive. These rebuilds can occur at the same time.
Use for office automation and online customer service that requires fault tolerance.
Use for any application that has high read request rates but low write request rates.
Benefits Provides data redundancy, high read rates, and good performance in most
environments. Each RAID 6 set can survive the loss of two drives or the loss of a
drive while another drive is being rebuilt. RAID 60 provides the highest level of
protection against drive failures of all of the RAID levels. The read performance is
similar to that of RAID 50, though random reads in RAID 60 might be slightly faster
because data is spread across at least one more disk in each RAID 6 set.
1-16
Cisco UCS Servers RAID Guide
OL-26591-01
Chapter 1 RAID Overview
Segment 1
Segment 8
Segment 2
Segment 7
Segment 10
Segment 5
Parity (P1–P2)
Parity (Q11–Q12)
Parity (Q1–Q2)
Segment 11
Segment 12
Parity (P15–P16)
Segment 15
Segment 16
Parity (Q15–Q16)
Segment 3
Segment 6
Segment 4
Parity (P9–P10)
Parity (Q9–Q10)Parity (P11–P12)
Segment 9
Parity (P13–P14)
Segment 14
Segment 13
Parity (Q13–Q14)
RAID 6
RAID 6
RAID 0
Parity (Q3–Q4)
Parity (P3–P4)
Parity (Q5–Q6)
Parity (P5–P6)
Parity (P3–P4)
Parity (Q3–Q4)
RAID
60
Note Parity is distributed across all drives in the drive group.
RAID Levels
Table 1-11 RAID 60 Overview (continued)
Features Description
Limitations Not well suited to tasks using many writes. A RAID 60 virtual drive has to generate
two sets of parity data for each write operation, which results in a significant decrease
in performance during writes. Drive performance is reduced during a drive rebuild.
Environments with few processes do not perform as well because the RAID overhead
is not offset by the performance gains in handling simultaneous processes. RAID 6
costs more because of the extra capacity required by using two parity blocks per
stripe.
Drives Two to 8 equal spans of RAID 6 drive groups containing 3 to 32 drives each (limited
by the maximum number of devices supported by the controller.)
Figure 1-12 RAID 60 Virtual Drive Example
Fault Tolerance
OL-26591-01
Fault tolerance is the capability of the subsystem to undergo a drive failure or failures without
compromising data integrity and processing capability. The RAID controller provides this support
through redundant drive groups in RAID levels 1, 5, 6, 10, 50, and 60. The system can operate properly
even with a drive failure in a drive group, although performance might be degraded to some extent.
• A RAID 1 drive group has two drives and can tolerate one drive failure.
• A RAID 5 drive group can tolerate one drive failure in each RAID 5 drive group.
• A RAID 6 drive group can tolerate up to two drive failures.
• Each spanned RAID 10 virtual drive can tolerate multiple drive failures as long as each failure is in
a separate drive group.
• A RAID 50 virtual drive can tolerate two drive failures as long as each failure is in a separate drive
group.
• RAID 60 drive groups can tolerate up to two drive failures in each drive group.
Note RAID level 0 is not fault tolerant. If a drive in a RAID 0 drive group fails, the whole virtual drive (all
drives associated with the virtual drive) fails.
Cisco UCS Servers RAID Guide
1-17
Generic Drive Replacement Procedure
Fault tolerance is often associated with system availability because it allows the system to be available
during the failures. However, it is also important for the system to be available during the repair of the
problem.
Hot spares are important in fault tolerance; see Hot Spares, page 1-4 for more information.
Auto-rebuild allows a failed drive to be replaced and the data automatically rebuilt by hot swapping the
drive in the same drive bay. See Hot Swap, page 1-6 for more information. The RAID drive group
continues to handle requests while the rebuild occurs.
Generic Drive Replacement Procedure
Note B-series blade servers are shown but the mechanical features (release button, eject lever) are the same
for most B-series and C-series servers.
Removing a Drive from a Server
Chapter 1 RAID Overview
Step 1 Push the button to release the ejector, fully extend the ejection lever and then pull the hard drive from its
slot. See Figure 1-13.
Figure 1-13 Removing the Drive
Step 2
Step 3 Install a blank faceplate (N20-BBLKD) to keep dust out of the server if the slot will remain empty.
Place the hard drive on an antistatic mat or antistatic foam if you are not immediately reinstalling it in
another blade server.
1-18
Cisco UCS Servers RAID Guide
OL-26591-01
Chapter 1 RAID Overview
Installing a Drive in a Server
Step 1 Place the hard drive lever into the open position by pushing the release button (see Figure 1-14).
Figure 1-14 Installing a Hard Drive in a Blade Server
Platform-Specific RAID and Drive Procedures
Step 2
Step 3 Push the hard drive lever into the closed position.
Gently slide the hard drive into the opening in the blade server until it seats into place.
If you need to move a RAID cluster, see the Moving a RAID Cluster section of the “Troubleshooting
Server Hardware” chapter of the Cisco UCS Troubleshooting Guide.
Platform-Specific RAID and Drive Procedures
B-series RAID and supported drive information that was previously in the software configuration,
hardware installation and service, and troubleshooting guides is repeated in this guide. B series servers
all have onboard RAID controllers that cannot be removed or upgraded. Only software configuration and
drive operations appropriate for that server’s controller are possible.
Supported RAID controllers for all models are listed in RAID Controllers in UCS Servers, page 3-10.
The C-Series hardware installation guides each have a “RAID Considerations” appendix that provides
information about supported RAID controllers and cables, plus cabling instructions specific to each
server model. See that documentation as needed at:
http://www.cisco.com/en/US/products/ps10493/prod_installation_guides_list.html
OL-26591-01
Cisco UCS Servers RAID Guide
1-19
Platform-Specific RAID and Drive Procedures
Chapter 1 RAID Overview
1-20
Cisco UCS Servers RAID Guide
OL-26591-01
CHA P T ER
2
Using Cisco Integrated Management Controller and Cisco UCS Server Configuration Utility for RAID Monitoring and Configuring
This chapter provides information about monitoring and configuring your RAID controller in your Cisco
Integrated Management Controller (CIMC) and Cisco UCS Server Configuration Utility. The Cisco
C-Series servers have built-in monitoring and configuration tools for storage, including RAID.
This chapter contains the following sections:
• Cisco Integrated Management Controller—Viewing Storage Properties, page 2-1
• Cisco UCS Server Configuration Utility—RAID Configuration, page 2-2
Note The tools and software referred to in this chapter are used only in C-series rack-mounted servers that are
not integrated with Cisco UCS Manager.
Cisco Integrated Management Controller—Viewing Storage Properties
CIMC is the management service for the C-Series servers and runs within the server.
You can use a web-based GUI or Secure Shell-based CLI to access, configure, administer, and monitor
the server. Almost all tasks can be performed in either interface, and the results of tasks performed in
one interface are displayed in another.
The configuration information for CIMC is located in the Cisco UCS C-Series Rack-Mount Servers
Configuration Guide and the Cisco UCS C-Series Rack-Mount Servers CLI Configuration Guide. For
details, see the guide that applies to the release that you are using.
A complete list of GUI and CLI configuration guides can be found here: Cisco UCS C-Series
Configuration Guides.
The following information is included:
• Storage adapters—Including all MegaRAID and Cisco Flexible Flash controllers.
• Controller information—that include the following:
–
PCI information
–
Manufacturing information
Cisco UCS Servers RAID Guide
OL-26591-01
2-1
Chapter 2 Using Cisco Integrated Management Controller and Cisco UCS Server Configuration Utility for RAID
Cisco Integrated Management Controller—Viewing Storage Properties
–
Running and startup firmware image information
–
Virtual and physical drive counts
–
General settings
–
Capabilities
–
Hardware configuration
–
Error counters
• Physical drive information—Including general drive information, identification information, and
drive status.
• Virtual drive information—Including general drive information, RAID information, and physical
drive information.
• Battery backup unit information (does not apply to Cisco Flexible Flash).
Cisco UCS Server Configuration Utility—RAID Configuration
You can use the RAID Configuration section in the Cisco UCS Server Configuration Utility document
to configure your system RAID controllers.
RAID levels supported by SCU are RAID 0, 1, 5, and 6.
The latest documentation can be found here: Cisco UCS Server Configuration Utility, Release 3.0 User
Guide.
If your system has multiple RAID controllers, Cisco UCS Server Configuration Utility displays a list of
all available RAID devices. This feature is described in the Server Configuration section.
Three types of RAID configurations can be set up using Cisco UCS Server Configuration Utility. This
feature is documented in the RAID configuration section.
• Automatic setup with redundancy
• Automatic setup without redundancy
• Create custom or multiple RAID arrays
2-2
Cisco UCS Servers RAID Guide
OL-26591-01
CHA P T ER
3
Using Cisco UCS Manager for RAID Configuring and Monitoring
This chapter describes monitoring and configuring your RAID controller using Cisco UCS Manager. The
Cisco B-Series servers have built-in monitoring and configuration tools for storage, including RAID.
This chapter contains the following sections:
• Cisco UCS Manager Configuration, page 3-1
• Server Disk Drive Monitoring, page 3-7
• RAID Controllers in UCS Servers, page 3-10
Note Cisco UCS Manager is used both with B-series blade servers and C-series rack servers that have been
integrated.
Cisco UCS Manager Configuration
Cisco UCS Manager interfaces with the LSI controllers and software and creates RAID configurations
as part of creating local disk configuration policies, which allow the same configuration steps to be
applied to many servers at once.
Local Disk Configuration Policy
This policy configures any optional SAS local drives that have been installed on a server through the
onboard RAID controller of the local drive. This policy enables you to set a local disk mode for all
servers that are associated with a service profile that includes the local disk configuration policy.
The local disk modes include the following:
• No Local Storage—For a diskless server or a SAN-only configuration. If you select this option, you
cannot associate any service profile that uses this policy with a server that has a local disk.
• RAID 0 Striped—Data is striped across all disks in the array, providing fast throughput. There is no
data redundancy, and all data is lost if any disk fails.
• RAID 1 Mirrored—Data is written to two disks, which provides complete data redundancy if one
disk fails. The maximum array size is equal to the available space on the smaller of the two drives.
• Any Configuration—For a server configuration that carries forward the local disk configuration
without any changes.
OL-26591-01
Cisco UCS Servers RAID Guide
3-1
Cisco UCS Manager Configuration
• No RAID—For a server configuration that removes the RAID and leaves the disk MBR and payload
unaltered.
• RAID 5 Striped Parity—Data is striped across all disks in the array. Part of the capacity of each disk
stores parity information that can be used to reconstruct data if a disk fails. RAID 5 provides good
data throughput for applications with high read request rates.
• RAID 6 Striped Dual Parity—Data is striped across all disks in the array, and two parity disks are
used to provide protection against the failure of up to two physical disks. In each row of data blocks,
two sets of parity data are stored.
• RAID10 Mirrored and Striped— RAID 10 uses mirrored pairs of disks to provide complete data
redundancy and high throughput rates.
You must include this policy in a service profile, and that service profile must be associated with a server
for the policy to take effect.
Guidelines for all Local Disk Configuration Policies
Before you create a local disk configuration policy, consider the following guidelines:
• No Mixed HDDs and SSDs
Mixing HDD and SSDs in a single server or RAID configuration is not supported.
Chapter 3 Using Cisco UCS Manager for RAID Configuring and Monitoring
• Do Not Assign a Service Profile with the Default Local Disk Configuration Policy from a B200 M1
or M2 to a B200 M3
Due to the differences in the RAID/JBOD support provided by the storage controllers of B200 M1
and M2 servers and those of the B200 M3 server, you cannot assign or reassign a service profile that
includes the default local disk configuration policy from a B200M1 or M2 server to a B200 M3
server. The default local disk configuration policy includes the Any Configuration or JBOD modes.
• Impact of Upgrade to Release 1.3(1i) or Higher
An upgrade from an earlier Cisco UCS firmware release to release 1.3(1i) or higher has the
following impact on the Protect Configuration property of the local disk configuration policy the
first time servers are associated with service profiles after the upgrade:
• Unassociated Servers
After you upgrade the Cisco UCS domain, the initial server association proceeds without
configuration errors whether or not the local disk configuration policy matches the server hardware.
Even if you enable the Protect Configuration property, Cisco UCS does not protect the user data on
the server if there are configuration mismatches between the local disk configuration policy on the
previous service profile and the policy in the new service profile.
Note If you enable the Protect Configuration property and the local disk configuration policy
encounters mismatches between the previous service profile and the new service profile, all
subsequent service profile associations with the server are blocked.
• Associated Servers
3-2
Any servers that are already associated with service profiles do not reboot after the upgrade. Cisco
UCS Manager does not report any configuration errors if there is a mismatch between the local disk
configuration policy and the server hardware.
Cisco UCS Servers RAID Guide
OL-26591-01
Loading...