Re: [linux-lvm] Device mapper problems..

[Lars Ellenberg <Lars.Ellenberg@linbit.com>]

/ 2005-09-16 02:23:46 +0300
\ Suleyman Kutlu:

> Two VGs.
> 
> systemvg on /dev/sda4
> datavg on /dev/sdb1
> 

slightly moving the chunks around in your mail,
so it is more obvious...

> What I am trying to do is:
> 
> - At least get the directory contents of the filesystem
>   /dev/datavg/snk2lv inorder to know what I have lost.
>   Is it possible to get this with jfsutils ??  Any experience ?

hm...

> - If there is a way to fix-up the device-mapper tables and get my
>   filesystems back, it is ofcourse welcome.

well, comparing this:

> ls -la /dev/mapper
> total 124
> drwxr-xr-x   2 root root    4096 Sep 16  2005 .
> drwxr-xr-x  36 root root  118784 Sep 16 01:49 ..
> crw-------   1 root root  10, 63 Sep 16  2005 control

> brw-------   1 root root 253,  0 Jun  5 03:24 systemvg-optlv
> brw-------   1 root root 253,  1 Jun  5 03:25 systemvg-varlv
> brw-------   1 root root 253,  1 May 10 03:08 systemvg-rootlv
> brw-------   1 root root 253,  2 Jun  5 03:26 systemvg-tmplv
> brw-------   1 root root 253,  3 Jun  5 03:26 systemvg-usrlv
> brw-------   1 root root 253,  4 Jun  5 03:27 systemvg-temp

> brw-------   1 root root 253,  6 Jul 16 20:32 datavg-rootlv
> brw-------   1 root root 253,  7 Jul 16 22:40 datavg-snk2lv
> brw-------   1 root root 253,  8 Sep 16  2005 datavg-backup

> dmsetup ls output is:
> 
> systemvg-optlv (253, 0)
> systemvg-tmplv (253, 1)
> systemvg-usrlv (253, 2)
> systemvg-varlv (253, 3)
> systemvg-temp  (253, 4)
> systemvg-rootlv(253, 5)

> datavg-rootlv  (253, 6)
> datavg-snk2lv  (253, 7)
> datavg-backup  (253, 8)


for a start,
we see that the device nodes for -optlv and -temp are correct,
and the datavg seems correct.

but 253,1 apears two times in the listing, and 253,5 is missing...

recreate those nodes with
# dmsetup mknodes

or by hand with:
# cd /dev/mapper
# rm systemvg-{varlv,rootlv,tmplv,usrlv}
# mknod systemvg-tmplv   b 253 1
# mknod systemvg-usrlv   b 253 2
# mknod systemvg-varlv   b 253 3
# mknod systemvg-rootlv  b 253 5

now, how this could happen is an other question.

note that maybe the mapping of names to minors is still wrong.
but at least all of the devices should be there again;
(253,5) was missing completely before.

hope that gets you one step further.

-- 
: Lars Ellenberg                                  Tel +43-1-8178292-0  :
: LINBIT Information Technologies GmbH            Fax +43-1-8178292-82 :
: Schoenbrunner Str. 244, A-1120 Vienna/Europe   http://www.linbit.com :