XFS_REPAIR on LVM partition

[Dave Chinner]

[ cc'd the XFS list again - please keep problem triage on the public
lists so that more than one person can help you. ]

On Mon, Dec 16, 2013 at 02:53:03PM -0200, Rafael Weingartner wrote:
> Today, I let the command xfs_repair /dev/... ran till it finished, I got
> the following messages:
> 
> Phase 1 - Find and verify superblock ....
> > Could not verify primary superblock - not enough secondary superblocks
> > with matching geometry!!

The primary superblock dump looked valid, but it it couldn't find
matching secondary superblocks from the contents of the primary that
it found.

> > attempting to find a secondary superblock.....
> > ...
> > ..
> > ...
> > ...
> > found candidate secondary superblock....
> > unable to verify superblock, continuing....

And it found blocks with the correct superbloc magic numbers, but
they don't match the primary superblock that was found.

> > found candidate secondary superblock....
> > unable to verify superblock, continuing...
> > ...
> > ...
> > ..............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................Sorry,
> > could not find valid secondary superblock
> > Exiting now.
> 
> 
> Should I upgrade the xfsprogs and try to run the xfs_repair again?
> Or does that message mean that there is no way of recovering the filesystem?

It's still possible to recover, but more info is needed first.
Can you get xfs_db to dump the primary and a couple of secondary
superblocks?

# xfs_db -c "sb 0" -c p -c "sb 2" -c p -c "sb 7" -c p <dev>

And post the output?

Cheers,

Dave.
-- 
Dave Chinner
david at fromorbit.com