RAID 5 Recovery

therealnerd2 · 29 Apr 2009 at 19:13

Hi All,

Running 4x500GB drives in RAID 5 on a Dell/HP/Adaptec 2610SA when the controller seemed to go a bit funny, and decided only 2 drives were detected. Replaced the controller and all drives now appear, but it seemingly cannot detect an array. Looking in an array manager and the 'metadata' seems to be there, but no array is detected, and "verification" doesn't help either.

Anyone know any tricks to rig the array back into action? Hack into the metadata somehow?

Thanks,
Nerd2

iaind · 29 Apr 2009 at 23:39

In most cases array configuration data is stored on disk rather than on the controller, so povided all the disks are good and the controller is the same, the array should be detected.

I'd be inclined to think that one of the disks is on its way out - I'd be inclined to power it down and call a data recovery specialist if it's critical. I'd be interested to know the details of "gone a bit funny" though...

therealnerd2 · 1 May 2009 at 08:55

iaind said:
In most cases array configuration data is stored on disk rather than on the controller, so povided all the disks are good and the controller is the same, the array should be detected.

I'd be inclined to think that one of the disks is on its way out - I'd be inclined to power it down and call a data recovery specialist if it's critical. I'd be interested to know the details of "gone a bit funny" though...

Thanks. The previous controller refuses to detect drives on 4 of it's 6 ports. However I can rotate the disks and see they are all fine.

The problem is with the firmware on the new card. Turns out at some point Adaptec moved the location of the metadata on the drive so the newer firmware on the new card doesn't detect the old array. I'm trying (struggling) to regress the firmware on the new drive to that of the old one.

neil_g · 1 May 2009 at 15:03

can you not recreate the array and restore from tape?

Skidilliplop · 1 May 2009 at 15:27

I'd have said the same thing. Though I was afraid there might be the response "what tape" then I would cry

therealnerd2 · 8 May 2009 at 16:07

Skidilliplop said:
Though I was afraid there might be the response "what tape" then I would cry

Who me?

For the record I simply used a Raid reconstructor to identify the arrangement, block size etc of the array - and then just recreated the array on the new card. There is a small amount of corruption but the data is 99% recoverable.