[OpenAFS] Re: recover data from corrupted volume

Andrew Deason adeason@sinenomine.net
Wed, 16 Jan 2013 15:45:58 -0600

On Wed, 16 Jan 2013 19:11:39 +0100
Stephan Wiesand <stephan.wiesand@desy.de> wrote:

> On Jan 16, 2013, at 18:25 , Dimitris Z wrote:
> > 01/16/2013 17:14:45 totalInodes 6446

Presumably you have at least some data there. The salvager found a bunch
of inodes relevant to that volume, so you certainly haven't lost
everything. But it probably deleted them all on salvage because the
volume metadata is screwed up.

> If there are remnants left, you should find them in AFSIDat/K1/Kz++U .
> If you can't find that directory, look for the files named
> zzzz5Mx1++0, zzzz9Mx1++0, zzzzDMx1++0, zzzzPMx1++0, possibly in
> lost+found. If you can't find any of those, I'm out of ideas/hope.

If it's not clear, look at this stuff before you salvage. For the most
part, the files in AFSIDat/K1/Kz++U are plain file blobs; there's no
structure or mangling or anything like that. The exceptions are the
metadata files in the dir called 'special', and the directory blobs. The
'special' files you can easily skip by just not looking at the 'special'
directory, but the directory blobs look like normal files. You could
filter out the directory blobs I think based on the filename, but I'd
have to think about how specifically to do that.

If you want to get back the directory structure and filenames and all
that, it's may still be possible, but you need to do some work messing
around with the volume metadata. That's probably not worth it if you're
fine with getting files back without their name or dir structure.

Andrew Deason