Disk failed in ZFS pool

[dznunn]

Hi

I've just started a new job and my new employer is using FreeNAS. There is no hardware RAID, no software RAID just a zfs pool containing 4 disks. One of these disks has failed, I can boot the box into single user mode and see the 3 remaining disks.

My question is, is there a way to recover useful data from the remaining disks? I'm assuming that because the disks are in a zfs pool then the data is striped across all the disks so I doubt I can recover much, if anything.

Thanks for any help in advance

 

[Ericloewe]

A single pool with 4 single-disk vdevs? The data is gone. There's no fixing that.

If they're individual pools, you can recover everything from the other disks.

Make sure you know exactly how the disks are setup. If you need a manual, here's a link to Cyberjock's guide.

Whatever the case, please do not leave valuable data on a simple set of striped disks! Or even individual, non-striped disks for that matter.

 

[dznunn]

That's what I thought, I just needed confirmation. The pool was setup sometime last year by a predecessor.

I'll read through Cyberjock's guide before rebuilding.

Thanks for your reply.

 

[danb35]

Four disks in a ZFS pool could be RAIDZ, mirrored, or just striped. When you're booted into single user mode, what's the output of "zpool status"?

 

[dznunn]

Just to clarify, this is what the zpool status showed before the disk completely failed. Now the zpool status output shows nothing.

[root@NAS01] /etc/zfs# zpool status REDNAS-Array-1
pool: REDNAS-Array-1
state: ONLINE
status: One or more devices has experienced an error resulting in data
corruption. Applications may be affected.
action: Restore the file in question if possible. Otherwise restore the
entire pool from backup.
see: http://illumos.org/msg/ZFS-8000-8A
scan: scrub repaired 0 in 1h7m with 3 errors on Sun May 4 01:07:07 2014
config:

NAME STATE READ WRITE CKSUM
REDNAS-Array-1 ONLINE 0 0 0
gptid/716abe5e-fea2-11e2-91cd-00e081787a96 ONLINE 0 0 0
gptid/72032b2a-fea2-11e2-91cd-00e081787a96 ONLINE 0 0 0
gptid/729ac5dc-fea2-11e2-91cd-00e081787a96 ONLINE 0 0 0
gptid/7334895d-fea2-11e2-91cd-00e081787a96 ONLINE 0 0 0

errors: 1262 data errors, use '-v' for a list
[root@NAS01] /etc/zfs#

 

[cyberjock]

Ow.. that's a striped pool. If you guys are willing to pay for some recovery, I have had good luck with recovering pools in similar situations. PM me if you want to talk prices and stuff. You personally wouldn't want to pay it, but it's definitely not horribly unreasonable. :P