IBM Netfinity ServeRAID-4H Ultra160, Справочник пользователя

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Rebuilding a defunct drive
A physical drive is defunct when there is a loss of communication between the
controller and the physical drive. This can be caused by any of the following:
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An improperly connected cable, physical drive, or controller
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Loss of power to a drive
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An improperly assembled SCSI channel in an unsupported configuration
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A defective cable, backplane, physical drive, or controller
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Connecting unsupported SCSI devices (such as tape drives) to the same SCSI
channel used for an array.
In each case, after the communication problem is resolved, a rebuild operation is
required to reconstruct the data for the device in its disk array. The ServeRAID
controllers can reconstruct RAID level-1 and RAID level-5 logical drives, but they
cannot reconstruct data stored in RAID level-0 logical drives because RAID level-0
is not redundant.
To prevent data-integrity problems, the ServeRAID controllers set the RAID level-0
logical drives in the effected array to blocked during the rebuild operation for RAID
level-1 or RAID level-5. After the rebuild operation completes, you can unblock the
RAID level-0 logical drives, and access them once again. Remember, however, that
the RAID level-0 logical drives might contain damaged data.
Note: For logical drives in an IBM ServeRAID Cluster Solution:
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Because shared logical drives can have only one logical drive for each
array, blocking a RAID level-0 logical drive during a Rebuild operation
does not apply to shared logical drives.
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Because non-shared logical drives can have more than one logical drive
for each array, blocking a RAID level-0 logical drive during a Rebuild
operation does apply to non-shared logical drives.
Steps for recovering from defunct drives
If the defunct drives are not part of an array, contact your IBM service
representative.
If the defunct drives are part of an array, do the following:
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If more than one physical drive in an array is defunct, contact your IBM service
representative.
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If a rebuild operation is in progress, wait until the rebuild is complete.
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If a rebuild is not in progress and only one physical drive in the array is defunct,
do the following:
1. Verify the cables, physical drives, and controllers are installed properly.
2. Attempt to rebuild the defunct physical drive by performing a Hot-Swap
Rebuild. Refer to “Rebuilding a hot-swap drive” for instructions.
3. If the Hot-Swap Rebuild fails, contact your IBM service representative.
Rebuilding a hot-swap drive
A Hot-Swap Rebuild refers to a Rebuild operation that is started by the ServeRAID
controller when it detects that a drive that is part of an array and in the defunct
state has been removed and reinserted on the SCSI cable or backplane. The
reinsertion of the physical drive, whether it is the same drive or a new drive, will
trigger the ServeRAID controller to start the rebuild operation. During the rebuild
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IBM
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Netfinity
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User’s Reference: ServeRAID
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-4H Ultra160 SCSI Controller