RAID 5 data recovery
WOT a SAGA! briefly I have 5 scsi disks which were in a healthy computer till it died spectaularly - one disk appeared to have failed. The hardware engineer replaced it - no joy there. After a lot of tooing and froing he ended up trying to reformat the remaining 4 and putting on win2000. But didnt work, and neither did the backup. Well, we got back 80%! The server ended up with new m'board, RAID controller, backplane and disks to give you an idea of the extent of the problem. But is there any hope of getting any of the missing 20%, or anything at all? I have an old (NT4) server i can put the disks (or disk) in and my idea is to boot from Ubuntu Rescue re-mix and run photorec or foremost or both. Am I wasting my time? Is there another method? Other software? Do i need to try all five disks at once?
Any leads/suggestions gratefully received.
AndrewN
I'm not sure of what you are
I'm not sure of what you are describing.
RAID 5 is mirrored, which means your data is in more than one place. If one disk of a RAID 5 array went kaput, you should still be able to access all your data. Are you sure it was raid 5? (mirrored?)
Again, if it was indeed RAID5, the data is striped, and the files are not contiguous on one single drive, so you would need to use all five disks at once.
raid 5 = striped with
raid 5 = striped with distributed parity. it looks kind of like this on 4 disks:
DISK1 DISK2 DISK3 DISK4
block1 block2 block3 parity(1-3)
parity(4-6) block4 block5 block6
block7 parity(7-9) block8 block9
... ... ... ...
so actually you need the 4 surviving disks...and a controller or software that can read the metadata on the disks in order to find the array
Ooops! I meant to say all
Ooops! I meant to say all *four* disks....