From: Shaya Potter <spotter@gmail.com>
To: linux-raid@vger.kernel.org
Subject: recovering from raid5 corruption
Date: Sun, 29 Apr 2012 18:38:29 -0400 [thread overview]
Message-ID: <4F9DC2E5.1090509@gmail.com> (raw)
somehow my raid5 got corrupted in the contexts of a main disk failure
(which wasn't raid related).
compounding this issue was that I had already had one disk in the raid5
go bad and was in the process of getting it replaced.
this raid array was 5 disks.
What I mean by corrupted is that the superblock of 3 of the remaining 4
devices seemed to have been wiped out (i.e. had a UUID of all 0s, though
still enough that it knew it was part of an md device)
now, the one whose superblock seems fine, places it at position disk 3
(of 0-4) and the missing disk at disk 2.
this would imply that there are only 6 permutations possible for the
other 3 disks. (even if that assumptions is wrong, there are only 120
permutations possible, which I should easily be able to iterate over).
further compounding this, is that there were 2 LVM logical disks on the
physical raid device.
I've tried being cute and trying all 6 permutations to force recreate
the array, but lvm isn't picking up anything. (pvscan/lvscan/lvmdiskscan)
The original raid had a version of 0.90.00 (created in 2008), while the
new one has a version 1.20.
have I ruined any chances of recovery by shooting in the dark with my
cute attempts, am I SOL or is there a better/proper way I can try to
recover this data?
Luckily for me, I've been on a backup binge of late, but there still
about 500-1TB of stuff that wasn't backed up.
thanks, any help would be appreciated.
next reply other threads:[~2012-04-29 22:38 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-04-29 22:38 Shaya Potter [this message]
2012-04-29 22:52 ` recovering from raid5 corruption NeilBrown
2012-04-29 23:29 ` Shaya Potter
2012-04-29 23:41 ` Shaya Potter
2012-04-29 23:44 ` NeilBrown
2012-04-29 23:45 ` NeilBrown
2012-04-29 23:51 ` Shaya Potter
2012-04-30 0:46 ` Shaya Potter
2012-04-30 1:09 ` NeilBrown
2012-04-30 1:13 ` Shaya Potter
2012-04-30 6:29 ` Jan Ceuleers
2012-04-30 15:33 ` Shaya Potter
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4F9DC2E5.1090509@gmail.com \
--to=spotter@gmail.com \
--cc=linux-raid@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).