Attempting to Recover Failed RAID 10

Discussions on using the professional data recovery program R-STUDIO for RAID re-construction, NAS recovery, and recovery of various disk and volume managers: Windows storage spaces, Apple volumes, and Linux Logical Volume Manager.

Attempting to Recover Failed RAID 10

Post by shelzmike » Mon Mar 11, 2013 10:41 am

I have a huge problem. I do not know a whole lot about RAID, but we have a 4 disk RAID 10 setup before I ever arrived here. It is on an INTEL board, which I think it software RAID so of course problems there.
My raid 10 has 1 Volume, 2 Spans, with 2 disks each in them.

Today, disk 4 of RAID stated failed, so SPAN 1 was degraded. I repalaced the drive and rebooted then suddenly Disk 5, the second of the two drives in SPAN 1 stated failed, now the volume is inaccessible. I am not sure what has happened, but I desperately need this data back. It was suggested that I attempt to use R-Studio and was told it worked well.

I installed the demo for now to see what I could see and when I open the console, I do not see the drive listed that are in the RAID 10 - the 2 good ones (Span 0) or the two failed ones (Span 1).

If I understand correctly, I would essentially use R-Studio to build a virtual RAID from these drives, copy the data to another location and then rebuild the raid, copy data back over. Is that correct? If so, how do I go about this? And why can't I see the drives? both are spinning and I find it highly unlikely the data is fully lost because just before I swapped out the initial failed drive, all the data was accessable. I was told this is probably more of a controller issue than anything. Thanks.


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Re: Attempting to Recover Failed RAID 10

Post by Alt » Tue Mar 12, 2013 3:24 am

Yes, you're right - you need to create a virtual RAID in R-Studio and copy the files elsewhere, then rebuild the RAID (if the fault disks aren't hardware-faulty), and copy the files back.
1. You should be aware that your RAID is really 10, (that is, stripes of mirrors) rather than 01 (a mirror of stripes). Wikipedia may help: RAID and Nested RAID levels.
2. Then check whether the failed disks are from the same mirror set or not. If not, disconnect the failed drives from the computer, turn your RAID setup in the RAID controller BIOS into just separate disks. Write down the serial numbers of the disk in the controller. If the failed disks are in the same mirror set, only a professional data recovery specialist could help you.
3. Create a stripe set out of the healthy disks. If you need the parameters of the RAID, you may use this free program: ReclaiMe Free RAID Recovery.

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