Re: Trying to recover data from an XFS partition

[Eric Sandeen <sandeen@xxxxxxx>]

Giuseppe Argentieri wrote:
> Hi,
>
> Some days ago my hard disk started to show a sector failure in
> /dev/hda7, which is the only XFS partion:
>
> # mount /mnt/space
>
> Oct 11 23:34:30 freedom kernel: [4298615.381000] XFS mounting filesystem hda7
> Oct 11 23:34:35 freedom kernel: [4298619.894000] hda: dma_intr: status=0x51 { 
> DriveReady SeekComplete Error }
> Oct 11 23:34:35 freedom kernel: [4298619.894000] hda: dma_intr: error=0x40 { 
> UncorrectableError }, LBAsect=45035525, sector=45035525
> Oct 11 23:34:35 freedom kernel: [4298619.894000] ide: failed opcode was: unknown
> Oct 11 23:34:35 freedom kernel: [4298619.894000] end_request: I/O error, dev 
> hda, sector 45035525
> Oct 11 23:34:35 freedom kernel: [4298619.896000] I/O error in filesystem ("hda7") 
> meta-data dev hda7 block 0x7775ba       ("xlog_bread") error 5 buf count 512
> Oct 11 23:34:35 freedom kernel: [4298619.896000] XFS: failed to find log head
> Oct 11 23:34:35 freedom kernel: [4298619.896000] XFS: log mount/recovery 
> failed: error 5
> Oct 11 23:34:35 freedom kernel: [4298619.896000] XFS: log mount failed
> mount: /dev/hda7: can't read superblock
>
>
> I wish I could access my data before the whole disk fails.
> I don't know why there is a superblock error, since sector 45035525 is
> not the first in /dev/hda7

I think that "superblock" error is a generic one.  the kernel logs tell you 
what is really going on - xfs cannot read the log due to disk errors.

Try mount -o ro,norecovery and copy off what you can... you may hit problems as 
you copy, though, because if you didn't do a clean unmount then your filesystem 
will be inconsistent w/o log recovery.

-Eric