•
Availability of drive cache.
•
Brand, model, and age of the disks.
•
Amount of unused capacity on the disks.
•
Number of disks in the array (for RAID 5 and RAID ADG).
System performance is affected during the rebuild, and the system is unprotected against further
disk failure until the rebuild has finished. Therefore, replace disks during periods of low activity
when possible.
When automatic data recovery finishes, the Online/Activity LED of the replacement disk stops
flashing at 1 Hz and begins to glow steadily (if the disk is inactive) or flash irregularly (if the disk
is active).
CAUTION:
If the Online/Activity LED on the replacement drive does not light up while the
corresponding LEDs on other drives in the array are active, the rebuild process has abnormally
terminated. The amber Fault LED of one or more disks might also be illuminated. See
to determine what action you must take.
Abnormal termination of a rebuild
If the Online/Activity LED on the replacement disk ceases to be illuminated even while other disks
in the array are active, the rebuild process has abnormally terminated.
Table 19 Indications and Causes of Abnormal Rebuild Termination
Cause of abnormal termination
Observed condition
Case
One of the disks in the array has experienced an
uncorrectable read error.
None of the disks in the array has an illuminated
amber Fault LED.
1
The replacement disk has failed.
The replacement disk has an illuminated amber
Fault LED.
2
The disk with the illuminated Fault LED has now failed.
One of the other disks in the array has an
illuminated amber Fault LED.
3
Each of these situations requires a different remedial action, as described in the following sections.
Case 1: an uncorrectable read error has occurred
If an uncorrectable read error has occurred:
1.
Back up as much data as possible from the logical drive.
WARNING!
Do not remove the disk that has the media error. This causes the logical drive
to fail, which could result in data loss.
2.
Restore data from the backup. Writing data to the location of the unreadable sector often
eliminates the error.
3.
Remove and reinsert the replacement disk. This restarts the rebuild process.
If the rebuild process still terminates abnormally:
1.
Delete and recreate the logical drive.
2.
Restore data from the backup.
Case 2: the replacement disk has failed
Verify that the replacement disk is of the correct capacity and is a supported model. If these factors
are not the cause of the problem, use a different disk as the replacement.
Case 3: another disk in the array has failed
A disk that has recently failed can sometimes be made temporarily operational again by cycling
the server power:
Abnormal termination of a rebuild 107
