[SWLUG] RAID Array data recovery

[Matthew Moore]

justin wrote:
> On Thu, 2009-09-24 at 21:30 +0100, Matthew Moore wrote:
>> Hi all,
>>
>> I've been having a few problems with my RAID 5 array this evening.  The
>> array is three 500gb drives in a RAID 5 config, using MDADM.  /dev/sdb.
>> /dev/sdc & /dev/sdd and the array is /dev/md0.  This morning in a bit of
>> a hurry I forced a power down, which seems to have corrupted the
>> superblock of the array.  I've been unable to create a backup superblock
>> (e2fsck -b 32768 /dev/md0) and /dev/sdd doesn't have a valid partition
>> table.  So while the array runs fine, it won't mount.  I've tried to
>> create a new Raid autodetect partition on /dev/sdd, but that doesn't
>> seem to work.  So in rough order I've done:
> 
> you have added whole disk devices to the array, none of them will have
> valid partition tables as youve used whole disks not partitons within
> the disks.  any partition table you can see is an artefact.
> 
> does md0 appear to have a valid partition table ?
> if it does then that might be why you cant fsck it, because the
> filesystem doesnt appear at the start of the disk, you have to access
> the sub partiton of it,  is there a /dev/md0p1 or similar ?
> 
> or did you put LVM on md0 ?  (try pvdisplay)
> 

root at hugh:/home/matt# fdisk -l /dev/md0

Disk /dev/md0: 1000.2 GB, 1000215543808 bytes
255 heads, 63 sectors/track, 121602 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

    Device Boot      Start         End      Blocks   Id  System
/dev/md0p1               1       60801   488384001   fd  Linux raid
autodetect

Which is odd, as it ought to be a ext3 partition.  Is it possible to
recover the ext3 partition that is on there?

Haven't used LVM at all.

Cheers,

Matt