Adaptec 5325302057 User Manual page 152

Recovering from a Disk Drive Failure
Failed Disk Drive Not Protected by a Hot Spare
When a pool is not protected by a hot spare, if a disk drive in that pool fails, remove
and replace the failed disk drive. The controller detects the new disk drive and
begins to rebuild the pool.
For instance, when one of the disk drives fails in a RAID 1 pool, the pool is not
automatically rebuilt. The failed disk drive must be removed and replaced before
the pool can be rebuilt.
If the controller fails to rebuild the pool, check that the cables, disk drives, and
controllers are properly installed and connected.
Failure in Multiple Pools Simultaneously
If there's a disk drive failure in more than one pool at the same time (one failure per
pool), and the pools have hot spares protecting them, the controller rebuilds the
pools with these limitations:
• A hot spare must be of equal or greater size than the failed disk drive it's
replacing.
• Failed disk drives are replaced with hot spares in the order in which they failed.
(The pool that includes the disk drive that failed first is rebuilt first, assuming an
appropriate hot spare is available—see the previous bullet.)
If there are more disk drive failures than hot spares, see "Failed Disk Drive Not
Protected by a Hot Spare" on page 146.
Disk Drive Failure in a RAID 0 Pool
Because RAID 0 volumes do not include redundancy, if a disk drive fails in a RAID
0 pool, the data can't be recovered.
Correct the cause of the failure or replace the failed disk drives. Then, restore your
data (if available).
Multiple Failures in the Same Pool
Except in RAID 6 and RAID 60 pools, if more than one disk drive fails at the same
time in the same pool, the data can't be recovered.
Correct the cause of the failure or replace the failed disk drives. Then, restore your
data (if available).
In some instances, RAID 10 and RAID 50 pools may survive multiple disk
Note
drive failures, depending on which disk drives fail.
146 Snap Server 700i Series User's Guide