IBM SAS RAID Series, Руководство пользователя

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Chapter 6. SAS RAID controller maintenance
Ensure optimal performance of your controller by using these maintenance procedures.
To help avoid controller and disk array problems, use the following tips:
v
Perform a normal system shutdown before physically replacing or moving the RAID controller or
members of disk arrays. A normal shutdown of the system will flush the controller’s write cache and
remove dependencies between the controller and the disks. Powering off the PCI slot using concurrent
maintenance options in Hardware Service Manager (HSM) has the same effect as it would on a single
controller when the PWRDWNSYS command is used.
Note: Disks that are a Failed member of an Unprotected (exposed) disk array can be replaced and the
disk unit data rebuilt while the system continues to run. No system shutdown is required.
v
You can physically move disks from one controller to another. However, if the disks are members of a
disk array, be sure to move all the disks in the array as a group. Prior to attempting a disk movement,
ensure that the disk array is not in an Unprotected state because of a disk failure. The system/partition
must be powered off normally before disks are moved.
v When physically removing disks that are members of a disk array, remove the disks from the Auxiliary
Storage Pool (ASP) and then stop RAID on the disk array before removing the disks. This action
avoids loss of data and disk-array-related problems the next time that these disks are used. The
system/partition must be powered off normally before disks are physically removed.
v
Always use the Device Concurrent Maintenance option to remove and replace a disk.
v
If the load source disk is part of a disk array and the system fails to IPL because of a suspected disk
array problem, IPL the system/partition using D-IPL media (CD/DVD or SAVESYS media). Error Log
Analysis, and other tools are available on the Dedicated Service Tools menu to help determine and
resolve the problem with the disk array.
v
Do not attempt to correct problems by swapping controllers and disks unless you are directed to do so
by the service procedures. Use Error Log Analysis to determine what actions to perform, and when
appropriate, follow the appropriate Isolation Procedures for problem determination. If multiple errors
occur at approximately the same time, look at them as a whole to determine if there is a common
cause.
v
Do not confuse the cache directory card, which is a small rectangular card with round, button-shaped
batteries, for a removable cache card. The nonvolatile write cache memory is integrated into the
controller. The write cache memory itself is battery-backed by the large, rechargeable cache battery
pack. The cache directory card contains only a secondary copy of the write cache directory and no
cache data. Do not remove this card except under very specific recovery cases as described in the
Isolation Procedures.
v
Do not unplug or exchange a cache battery pack without following the procedures as outlined in this
section or in the Isolation Procedures. Failure to follow these procedures might result in data loss.
Rechargeable battery maintenance
Rechargeable battery maintenance tasks include displaying rechargeable battery information, forcing a
rechargeable battery error, and replacing the rechargeable cache battery pack.
Displaying rechargeable battery information
Use this procedure to display information about the controller’s rechargeable battery using the Hardware
Service Manager in the IBM
®
i operating system.
1. Sign on to the system with at least service level authority.
2. On the command line, type strsst. Press Enter.
© Copyright IBM Corp. 2009
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