Rebuilding Units - 3Ware 9550SXU-16ML User Manual

Rebuilding Units

If a hot spare is specified and a redundant unit degrades, an event notification
is generated and the hot spare dynamically replaces the failed drive in the
redundant unit without user intervention. The rebuild process will
automatically be launched as a background process at the next scheduled
time. If scheduling is turned off, the rebuild process will start almost
immediately (within a few minutes). If 3DM is running and E-mail
notification is enabled, an event notification will be sent to specified users
when the rebuild process starts and when it completes.
For 9550SX controllers, if Auto-Rebuild is enabled, the firmware will attempt
to rebuild a degraded unit with an available drive or a failed drive.
If desired, you can manually replace the drive, rescan the controller, and start
the rebuild process.
Manual rebuilds can be started from either 3BM or 3DM, although the rebuild
itself only happens when the operating system is running.
If multiple drives are faulted in a RAID 10 configuration, the drives are
rebuilt simultaneously. In a 4-drive RAID 10 configuration, up to two drives
can be rebuilt. In a 6-drive configuration, up to three drives can be rebuilt. In
an 8-drive configuration, up to four drives can be rebuilt. In a 12-drive
configuration, up to six drives can be rebuilt.
A RAID 50 unit can also sustain multiple drive failures, as long there is only
one failed drive in each RAID 5 set.
When a RAID 5 is running in Degraded mode, the missing data is
reconstructed from all non-degraded drives.
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Note : If both drives in a RAID 10 mirror set are faulted, the data is
not recoverable. Up to half of the drives in a RAID 10 unit can
become defective and still have the user data retained, as long as
the failed drives are only half of each mirrored pair.
If a rebuild fails, check the Alarms page for the reason. If
Note:
there was an ECC error on the source disk, you can force the
rebuild to continue by checking the Overwrite ECC Error policy on
the Controller Settings page in 3DM and then running Rebuild
again. This will cause uncorrectable blocks to be rewritten, but the
data may be incorrect. It is recommended that you execute a file
system check when the rebuild completes.
Rebuilding Units
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