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I have four (4) disks which are in RAID 0, but the (Lacie) hardware enclosure failed and I'm trying to recover the data stored. I'm now trying to rebuild the RAID to access the data stored, but can't seem to find a way.

I made an image for each disk with ddrescue to check for any errors and there weren't any, so I guess the disks are in good shape.

Checking with fdisk, as I've seen suggested, resulted in the following:

Disk: 1.img geometry: 30401/255/63 [488397168 sectors]
Signature: 0xFE01
        Starting       Ending
#: id  cyl  hd sec -  cyl  hd sec [     start -       size]
------------------------------------------------------------------------
1: 04  256  12  32 -  298  14   2 [ 708576768 - -1488818672] DOS FAT-16  
2: 52  840   6  33 -  256  64  50 [  19857458 -  872426031] CP/M or SysV
3: 30  256 167  48 -  904   6  37 [-1060025824 - 1880107055] <Unknown ID>
4: 06  442  10  14 -    8 184  46 [-671061216 - -1437243380] DOS > 32MB

Disk: 2.img geometry: 30401/255/63 [488397168 sectors]
Signature: 0x0
        Starting       Ending
#: id  cyl  hd sec -  cyl  hd sec [     start -       size]
------------------------------------------------------------------------
1: 00    0   0   0 -    0   0   0 [         0 -          0] unused      
2: 00    0   0   0 -    0   0   0 [         0 -          0] unused      
3: 00    0   0   0 -    0   0   0 [         0 -          0] unused      
4: 00    0   0   0 -    0   0   0 [         0 -          0] unused

Disk: 3.img geometry: 30401/255/63 [488397168 sectors]
Signature: 0x0
        Starting       Ending
#: id  cyl  hd sec -  cyl  hd sec [     start -       size]
------------------------------------------------------------------------
1: 00    0   0   0 -    0   0   0 [         0 -          0] unused      
2: 00    0   0   0 -    0   0   0 [         0 -          0] unused      
3: 00    0   0   0 -    0   0   0 [         0 -          0] unused      
4: 00    0   0   0 -    0   0   0 [         0 -          0] unused

Disk: 4.img geometry: 30401/255/63 [488397168 sectors]
Signature: 0xAA55
        Starting       Ending
#: id  cyl  hd sec -  cyl  hd sec [     start -       size]
------------------------------------------------------------------------
1: 07    0   1   1 - 1023 254  63 [        63 - 1953584262] HPFS/QNX/AUX
2: 00    0   0   0 -    0   0   0 [         0 -          0] unused      
3: 00    0   0   0 -    0   0   0 [         0 -          0] unused      
4: 00    0   0   0 -    0   0   0 [         0 -          0] unused 

By looking at this output, it seems to me that only 2 out of 4 disks were actually used by the RAID, probably writing sequentially.

Is there any way I can access the data stored on those disks?

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2 Answers

The data you're seeing with fdisk is nonsense. You need to reconstruct the RAID striping to get sensible data -- the drives only have a single partition table because they're only a single logical volume.

You need to figure out two things. First, the logical order of the disks. Second, the stripe size. Then you need to read a stripe from each disk in logical order and repeat to reconstruct the logical partition. There's a good chance the stripe size is either 512 bytes or 4KB.

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What you mean is nonsense? Could it be JOBD considering fdisk's output? –  Gurzo Feb 28 '12 at 11:24
    
You said in the question it was RAID 0. The output is consistent with that. –  David Schwartz Feb 28 '12 at 11:27
    
I know, but I'm still looking for a solution myself and wondered. You mean the output is consistent with a JOBD or a RAID? –  Gurzo Feb 28 '12 at 11:28
    
The output is consistent with RAID 0. You may be able to figure out the stripe size by looking for chunks of consistent data. If you see 512 bytes that go together, then the stripe size is likely 512 bytes. It could be any power of 2 between 512 bytes and 64KB. But it's likely 512 bytes to 16KB. –  David Schwartz Feb 28 '12 at 11:28
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Best way to recover data on a Raid 0 volume is to use the same exact raid hardware that created the array, firmware revision for the raid chip should be the same also, to insure a good outcome. Connecting all drives in the proper order to the exact same raid 0 hardware will allow you to mount the entire 4 disk volume and recover files. This is not always the easiest way.

Since the data is split between the discs, one disc by itself will not have any recoverable data, one caveat to this is raid 0 has a stipe size, no telling what it was, but any file equal to or smaller than the stripe size will only be stored on one drive as a whole file, this data may be recoverable without using the original or exact same raid controller hardware, but is not worth the risk to tamper with drives on an individual basis as this may compromise recovering the rest of the data.

Raid 0 data recovery is one of the more expensive recovery processes when you have to pay someone to do it, its not very easy to do but software based recovery solutions have become less expensive these days.

You might have a look at this

I would continue to work with images of the hard drives and not the physical hard drives when trying to recover, which sounds like what you have done so far.

.

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