HP Smart Array P600-Controller - Manual (Page 32)

32 HP Smart Array P600 Controller for Integrity Servers User Guide
Factors to consider before replacing hard drives
Before replacing a degraded drive:
• Open Systems Insight Manager 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 Systems Insight Manager 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.
In systems that use external data storage, be sure that the server is the first unit to
be powered down and the last to be powered back up. Taking this precaution
ensures that the system does not erroneously mark the drives as failed when the
server is powered up.
To minimize the likelihood of fatal system errors, take these precautions when
removing failed drives:
• Do not remove a degraded drive if any other drive in the array is offline (the
Online/Activity LED is off). In this situation, no other drive in the array can
be removed without data loss.
The following cases are exceptions:
– 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, as long as no two failed drives belong
to the same mirrored pair.
– When RAID 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/Activity LED on the front of the drive stops
blinking.)