Raid-5 recovery advice

[theastralmedic]

Firstly, I hope my post is appropriate. I something of a look around and a search, and I don't think this has been covered anywhere I can find, but I'm quite fallible.

Essentially my situation is that I had an array of four 320GB drives in RAID5, one of them dropped out of the array, I got a replacement and rebuilt it, but it seems another disk died while it was rebuilding. So at the moment I'm left with five disks, two of which are healthy, and three of which are in various states of disrepair. I've had a play round with some data recovery software, and successfully recovered a decent portion of the data from the new drive and the two remaining old ones, but much is corrupted, things like images being half available. Presumably these are things that were located in sectors where parity information wasn't written before the second failure.

At this point I'd like to try experimenting with recovering things using the other two drives, but I'm afraid my knowledge in this field is quite minimal. Would anyone be able to offer some suggestions as to how to proceed? I have backups of everything critical I had from well before the failure I mentioned above, so it's not absolutely vital to do this. I am however inclined to treat this as a learning curve to see if I can save myself a lot of time and effort going through and manually investigating, and replacing files.

Any advice, and/or redirections to a better place to ask are most appreciated;

Russell

[quasimodo]

Hello Russell,

1) First check the status of your 4 original drives.
In particular the 2 drives that dropped of the RAID set.

2) Download MHDD and follow FAQ or Manual for testing of drives.

3) We do this to determine the state of your failed drives, since we need al least 3 of the 4
for recovery.

4) After you tested the drives, I would recommend creating an Image (image file) of all
the healthy drives. There are several affordable application out there that will allow
you to create an image.

5) Use application to reconstruct RAID set. There are also several affordable applications
out there to acomplish this.

Good luck!

[theastralmedic]

Thank you for that. I've gotten my hands on MHDD, and I'll be doing a test as soon as I have some free time. Any further suggestions on what applications are best for steps four and five? I've had Raid Reconstructor recommended to me elsewhere, but the people on this forum seem especially knowledgeable, so I'd value any input.

[hddguy]

RAID reconstructor is a valid application to use, but only if used correctly, and assuming your RAID is a Windows based RAID. Download the trial version and see what results it gives you

[theastralmedic]

Thank you for the advice. I've just finished pulling data off two different combinations of drives, and I'll be trying a third in another PC soon. Basically everything important to me is safely written to other disks, and from now on I plan on having either triple, or just double redundant backups, still deciding on that one. One lesson learned there

Many thanks;

Russell