Re: where did my ata drives go?

[Rick Pasotto <rick@niof.net>]

On Sat, Sep 11, 2010 at 07:34:38PM +0200, Florian Kulzer wrote:
> On Sat, Sep 11, 2010 at 12:16:43 -0400, Rick Pasotto wrote:
> 
> > ERROR: superblocks chain: ambivalent result detected (2 filesystems)!
> 
> You seem to have vestigial signatures of other filesystems on the two
> partitions. You can use "wipefs" to list all filesystem signatures on a
> partition and also to remove the outdated one. (See the manpage and be
> careful not too delete the signature of the current ext3 filesystem.)

Here is what I did and the results:

niof:~# wipefs /dev/sdc1
offset               type
----------------------------------------------------------------
0x438                ext3   [filesystem]
                     LABEL: hdb1
                     UUID:  03c23684-dea8-458d-b04b-0ae8a056cb0d

0x52                 vfat   [filesystem]
                     LABEL: DISK3PART00
                     UUID:  5CD5-4461

niof:~# wipefs -o 0x52 /dev/sdc1
8 bytes [46 41 54 33 32 20 20 20] erased at offset 0x52 (vfat)
niof:~# wipefs /dev/sdc1
offset               type
----------------------------------------------------------------
0x438                ext3   [filesystem]
                     LABEL: hdb1
                     UUID:  03c23684-dea8-458d-b04b-0ae8a056cb0d

0x0                  vfat   [filesystem]
                     LABEL: DISK3PART00
                     UUID:  5CD5-4461

> As soon as there is only one signature left on each of the partitions,
> blkid and all the rest should work again.
> 
> Two other important tests are:
> 
>   findfs LABEL=hdb1
>   findfs UUID=03c23684-dea8-458d-b04b-0ae8a056cb0d
> 
> Both these commands should return "/dev/sdc1".

niof:~# findfs LABEL=hdb1
findfs: unable to resolve 'LABEL=hdb1'
niof:~# findfs UUID=03c23684-dea8-458d-b04b-0ae8a056cb0d
findfs: unable to resolve 'UUID=03c23684-dea8-458d-b04b-0ae8a056cb0d'

OK, just for kicks I then did:

niof:~# wipefs -o 0x0 /dev/sdc1
1 bytes [eb] erased at offset 0x0 (vfat)
niof:~# wipefs /dev/sdc1
offset               type
----------------------------------------------------------------
0x438                ext3   [filesystem]
                     LABEL: hdb1
                     UUID:  03c23684-dea8-458d-b04b-0ae8a056cb0d

0x1fe                vfat   [filesystem]
                     LABEL: DISK3PART00
                     UUID:  5CD5-4461

niof:~# wipefs -o 0x1fe /dev/sdc1
2 bytes [55 aa] erased at offset 0x1fe (vfat)
niof:~# wipefs /dev/sdc1
offset               type
----------------------------------------------------------------
0x438                ext3   [filesystem]
                     LABEL: hdb1
                     UUID:  03c23684-dea8-458d-b04b-0ae8a056cb0d


Looks like I needed to run 'wipefs' *three* times to get rid of the signature.

Both partitions now mount with either LABEL or UUID.

Thanks for all your help.

-- 
"You are merely not feeling equal to the tasks before you." -- Dale Carnegie
    Rick Pasotto    rick@niof.net    http://www.niof.net