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•
Open HPE Systems Insight Manager (HPE 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 HPE 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:
◦
If 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.
◦
If RAID 6 with Advanced Data Guarding (ADG) is used, two drives can fail simultaneously (and be replaced
simultaneously) without data loss.
◦
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:
◦
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.
◦
In RAID 6 with ADG configurations, any two drives in the array can be replaced simultaneously.
Automatic data recovery
If you replace a disk 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).
•
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 Advanced Data Guarding (ADG) configuration
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Troubleshooting
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