Drive procedures 24
Time required for a rebuild
The time required for a rebuild varies, depending on several factors:
•
The priority that the rebuild is given over normal I/O operations (you can change the priority setting
by using HPE SSA)
•
The amount of I/O activity during the rebuild operation
•
The average bandwidth capability (MBps) of the drives
•
The availability of drive cache
•
The brand, model, and age of the drives
•
The amount of unused capacity on the drives
•
For RAID 5 and RAID 6, the number of drives in the array
•
The strip size of the logical volume
CAUTION:
Because data rebuild time operates at the rate of 200GB/15 minutes, the system
could be unprotected against drive failure for an extended period during data recovery or a
drive capacity upgrade. When possible, perform rebuild operations only during periods of
minimal system activity.
When automatic data recovery has finished, the drive status LED changes from flashing green to solid
green.
If the drive status LED on the replacement drive changes to flashing or solid amber, the rebuild process
has terminated abnormally.
If an abnormal termination of a rebuild occurs, identify the cause and appropriate corrective steps in
"Abnormal termination of a rebuild."
Abnormal termination of a rebuild
If the activity LED on the replacement drive permanently ceases to be illuminated even while other drives
in the array are active, the rebuild process has terminated abnormally. The following table indicates the
three possible causes of abnormal termination of a rebuild.
Observation
Cause of rebuild termination
None of the drives in the array have an
illuminated amber LED.
One of the drives in the array has
experienced an uncorrectable read error.
The replacement drive has an
illuminated amber LED.
The replacement drive has failed.
One of the other drives in the array
has an illuminated amber LED.
The drive with the illuminated amber LED
has now failed.
Each of these situations requires a different remedial action.
Case 1: An uncorrectable read error has occurred.
1.
Back up as much data as possible from the logical drive.
CAUTION:
Do not remove the drive that has the media error. Doing so causes the logical
drive to fail.
2.
Restore data from backup. Writing data to the location of the unreadable sector often eliminates the
error.
3.
Remove and reinsert the replacement drive. This action restarts the rebuild process.
If the rebuild process still terminates abnormally:
1.
Delete and recreate the logical drive.