[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <50AA503D.2060503@redhat.com>
Date: Mon, 19 Nov 2012 09:29:01 -0600
From: Eric Sandeen <sandeen@...hat.com>
To: George Spelvin <linux@...izon.com>
CC: dreusser@...il.com, linux-ext4@...r.kernel.org
Subject: Re: Issue with bad file system
On 11/19/12 2:32 AM, George Spelvin wrote:
...
> "e2fsck -n" will only print errors and not change anything. It's
> always safe.
>
> Try "e2fsck -n -v /dev/md0" (given the dumpe2fs failure, I expect that
> will not work) and then try "e2fsck -n -v -b 32768 /dev/md0".
>
> I don't know what happened to your superblock, but if that's all that
> got trashed, recovery is actually quite straightforward and there's no
> risk of data loss. e2fsck will just print a huge number of "free blocks
> count wrong" messages as it fixes them.
>
> (However, that's a pretty big "if".)
>
>
> Another thing that would be useful is "dd if=/dev/md0 skip=2 count=2 | xxd"
> (or od -x if you don't have xxd). That will give a hex dump of the
> primary superblock, which might show the extent of the damage.
>
>
> If "e2fsck -n -b 32768" works, the way to repair it is to run it again
> without the "-n", but the -n output will say how bad it is.
Whoops, I replied without seeing these other replies; somehow threading
was broken w/ George's first reply.
Anyway - I would not go to e2fsck yet. I think your raid is mis-assembled.
I'd investigate that first. I'll look at the other output a bit more, but
for now, I'd stay away from fsck - just wanted to get that out there quick.
-Eric
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists