On 11/10/2011 10:23 AM, William Colls wrote:
[...]

the array was mounted as follows

mount -t ext3 /dev/md0p1 /opt/share

LVM was not installed on the old system, nor is it installed on the new machine

OK.

quoted

Please show a hexdump of the first 8k of /dev/md0p1.  That should give us a signature to hunt down.

00000000  fa b8 00 10 8e d0 bc 00  b0 b8 00 00 8e d8 8e c0 |................|
00000010  fb be 00 7c bf 00 06 b9  00 02 f3 a4 ea 21 06 00 |...|.........!..|
00000020  00 be be 07 38 04 75 0b  83 c6 10 81 fe fe 07 75 |....8.u........u|
00000030  f3 eb 16 b4 02 b0 01 bb  00 7c b2 80 8a 74 01 8b |.........|...t..|
00000040  4c 02 cd 13 ea 00 7c 00  00 eb fe 00 00 00 00 00 |L.....|.........|
00000050  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00 |................|
*
000001b0  00 00 00 00 00 00 00 00  17 29 06 00 00 00 00 01 |.........)......|
000001c0  01 00 83 fe ff ff 3f 00  00 00 01 14 54 57 00 00 |......?.....TW..|
000001d0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00 |................|
*
000001f0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 55 aa |..............U.|
00000200  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00 |................|
*
00002000

The signature is definitely not there for superblock 0, and it doesn't look like any other structure I'm familiar with.

Since you are confident it was ext3, try:
dumpe2fs |grep superblock

or:
dumpe2fs -f |grep superblock

That might find a backup superblock that can then be used with fsck.  See e2fsck(8), option "-b".

I would run e2fsck in read-only mode for each backup superblock attempted, to see how bad the situation is.  If its mostly clean, then it would be safe to proceed with the actual repair.

If none of this works, I'm out of ideas.  You'd probably want to ask for more help on the linux-ext4 mailing list.

Phil