RAID status: degraded or failed? is there help?

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Level 1

8 points

RAID status: degraded or failed? is there help?

We are using mac os sever 10.4.3. When we recently restarted the servers we noticed that 2 drives on each of the servers has yellow warning lights showing on the moitor software but not on the actual drives themselves. We have 2 servers one a G4 and the other a G5. The G4 has 2 drives and both are registering yellow, the G5 has 4 drivers with 2 registering yellow. The monitor says the drives are "degraded" but everything seems to be transferring and backing up fine. Should we do a backup and use Disk Utility to repair the degraded/damaged drives?

Mac OS Server Mac OS X (10.4.3) Processor 2 GHz G5 Memory 2 GB

Posted on Dec 27, 2006 9:25 AM

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Answer 1

Camelot

Level 9

58,365 points

Dec 27, 2006 2:11 PM in response to bipprepress

Should you? Absolutely.

Clearly something is wrong with the arrays. It's entirely possible for a RAID to degrade without a disk failure. If the disks are mirrored, for example, it's possible for the mirror to get out of sync where data isn't written to one drive or another. This causes the RAID to report as 'degraded' but you're not running a mirror until the RAID is repaired.

Backup your data (just in case) and repair the array, either by rebuilding or by replacing the drive if necessary.

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Answer 2

Dec 27, 2006 2:20 PM in response to bipprepress

You must have RAID 1 mirrored drives setup then and are running from the working disk of the mirrored pair.

Ofcourse you should fix these types of problems/failing disks.
Having recent backups is always a good thing. A RAID doesn't save you from human errors but it should prevent "downed" servers.

Your supposed to be able to repair a degraded mirror from within Disk Utility but I have only done it from the CLI (Terminal) diskutil.

If you do a : sudo diskutil checkraid

What do you get?

If the servers are updated from 10.3.x you can (if not done already) also update the RAID version from the older ver. 1 to ver. 2 available from 10.4.0-> using the command:
sudo diskutil convertraid

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