Troubleshooting 40
•
Open HP SIM and inspect the Error Counter window for each physical drive in the same array to
confirm that no other drives have any errors. (For details, refer to the HP SIM documentation on the
Management CD.)
•
Be sure that the array has a current, valid backup.
•
Use replacement drives that have a capacity at least as great as that of the smallest drive in the array.
The controller immediately fails drives that have insufficient capacity.
To minimize the likelihood of fatal system errors when removing failed drives, take the following precautions:
•
Do not remove a degraded drive if any other drive in the array is offline (the online LED is off). In this
situation, removing any other drive in the array causes data loss.
Exceptions:
o
When RAID 1+0 is used, drives are mirrored in pairs. Several drives can be in a failed condition
simultaneously (and they can all be replaced simultaneously) without data loss, if no two failed
drives belong to the same mirrored pair.
o
When RAID 6 with ADG is used, two drives can fail simultaneously (and be replaced
simultaneously) without data loss.
o
If the offline drive is a spare, the degraded drive can be replaced.
•
Do not remove a second drive from an array until the first failed or missing drive has been replaced
and
the rebuild process is complete. (The rebuild is complete when the online LED on the front of the drive
stops blinking.)
Exceptions:
o
In RAID 1+0 configurations, any drives that are not mirrored to other removed or failed drives can
be simultaneously replaced offline without data loss.
o
In RAID 6 with ADG configurations, any two drives in the array can be replaced simultaneously.
Automatic data recovery (rebuild)
When you replace a hard drive in an array, the controller uses the fault-tolerance information on the
remaining drives in the array to reconstruct the missing data (the data that was originally on the replaced
drive) and write it to the replacement drive. This process is called automatic data recovery, or rebuild. If fault
tolerance is compromised, this data cannot be reconstructed and is likely to be permanently lost.
If another drive in the array fails while fault tolerance is unavailable during rebuild, a fatal system error may
occur, and all data on the array is then lost. In exceptional cases, however, failure of another drive need not
lead to a fatal system error. These exceptions include:
•
Failure after activation of a spare drive
•
Failure of a drive that is not mirrored to any other failed drives (in a RAID 1+0 configuration)
•
Failure of a second drive in a RAID 6 with ADG configuration
Time required for a rebuild
The time required for a rebuild varies considerably, depending on several factors:
•
The priority that the rebuild is given over normal I/O operations (you can change the priority setting by
using ACU)
•
The amount of I/O activity during the rebuild operation
Summary of Contents for D6000 Disk Enclosure
Page 12: ...Customer self repair 12 ...
Page 13: ...Customer self repair 13 ...
Page 14: ...Customer self repair 14 ...
Page 18: ...Illustrated parts catalog 18 ...
