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Guillermo_Garcia

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RAID 5 problem with array of 4 disks.

I have a Dell PowerEdge 4400 server running Windows NT Server 4.0 and having a Dell PERC 3/Di controller.

This system has two arrays 0 for OS (RAID-1 functioning OK) and 1 for data (RAID-5)

Array 1 is not available and its members have this status:
Array Disk 1:0 Is ready            16.96 GB SCSI Port:1 Target ID:0 LUN:0 Seagate ST318451LC Rev 3
Array Disk 1:1 Is ready       16.96 GB SCSI Port:1 Target ID:1 LUN:0 Quantum ATLAS10K3_18_SCA 120G
Array Disk 1:2 Is Degraded       16.96 GB SCSI Port:1 Target ID:2 LUN:0 Seagate ST318453LC 6E03
Array Disk 1:3 Is Offline       16.96 GB SCSI Port:1 Target ID:3 LUN:0 Seagate ST318451LC 0003
Array Disk 1:4 Is ready       16.96 GB SCSI Port:1 Target ID:4 LUN:0 Seagate ST318203LC 0002

I tried to re-scan the data array and the amsnapin mmc replies with an "Array Manager - An unexpected error has occurred".

I added the 1:4 disk and tried to configure it as spare but the recovery process does not start. I also have replaced the offline drive with this one and the recovery does not start either.

I am concerned about this because I have a drive offline and other degraded. Are those two drives broken?

How can I fix the problem?

Can I run "Remove Orphan/Dead Disk Segments" on Array disk 1:2? And what about the offline?

Any help will be appreciated.

Thank you.
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Duncan Meyers
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Things aren't looking too rosy I'm afraid. Firstly, do you have a good set of backups?

The reason the recovery won't start is that you've lost 2 members out of a RAID 5 set. If you can ascertain which drive failed first, it may be possible to recover your data. In Array Manager, select the Events tab and look back through the event log to see when Disc 1:3 went Offline and when Disc 1:2 went Degraded. Can you post the logs here?

Once you know which drive failed second, you can try forcing the drive online. Beware!! If you select the wrong drive to force online you will irretreviably corrupt the data on the array, so make sure you select the correct drive. Also Beware!! Do *not* force both drives online unless you *know* that they went offline at precisely the same moment, or you will corrupt the data on the array

If the Force Online succeeds then you should be able to make Disc 1:4 into a Hotspare and the array will rebuild to the hotspare.
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Guillermo_Garcia

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Disc 1:2 was degraded first, then Disc 1:3 was degraded and then offline.

ASKER CERTIFIED SOLUTION
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Duncan Meyers
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