IBM 866251Y - Netfinity 5500 M20, Hardware Maintenance Manual, Page: 166 / 386

to Blocked during a Rebuild operation. After the Rebuild
operation completes, you can unblock the RAID level-0
logical drives, and access them once again. But
remember, the logical drive might contain damaged data.
(Refer to “Unblocking logical drives” on page 108 for more
information.)
Before you rebuild a drive, review the following guidelines
and general information.
Guidelines for the rebuild operation:
Ÿ
The replacement hard disk drive must have a
capacity equal to or greater than the failed drive.
Ÿ
If the hard disk drive being rebuilt is part of a RAID
level-0 logical drive, the RAID level-0 drive is blocked.
– You must unblock any RAID level-0 logical
drives at the end of the rebuild operation.
– If you use the Administration and Monitoring
program to initiate the rebuild operation, you can
unblock the blocked RAID level-0 drive when the
rebuild operation completes. (See “Unblocking
logical drives” on page 108 for more
information.)
Ÿ
Data in a logical drive with RAID level-0 is lost during
the rebuild operation. If you backed up the data
before the drive failed, you can restore the data to the
new drive.
General information about the rebuild
operation:
A physical hard disk drive can enter the rebuild state if:
Ÿ
You physically replace a defunct drive that is part of
the critical logical drive.
When you physically replace a defunct drive in a
critical logical drive, the ServeRAID adapter or
controller rebuilds the data on the new physical drive
before it changes the logical drive state back to Okay.
Ÿ
The ServeRAID adapter or controller adds a
hot-spare or a standby hot-spare drive to the array
and changes its state from Hot-Spare or Standby
Hot-Spare to Rebuilding.
Automatically rebuilding the defunct drive:
The ServeRAID adapter or controller will rebuild a defunct
drive automatically when all of the following conditions
exist:
Ÿ
The physical drive that failed is part of a RAID level-1
or RAID level-5 logical drive.
Ÿ
A hot-spare or standby hot-spare drive with a capacity
equal to or greater than the capacity of the defunct
drive is available the moment the drive fails.
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