[linux-lvm] Unable to mount LVM partition - table too small

[Luca Berra]

>
> I also don't remember ever seeing /dev/md0p1 before, just a /dev/md0

i guessed as much

> root at adam-desktop:~# mdadm --examine --scan --verbose
> ARRAY /dev/md0 level=raid5 num-devices=4 
> UUID=b5e0fcd0:cfadbb04:a5b6f22e:457f47ae
>    devices=/dev/sde,/dev/sdd,/dev/sdc,/dev/sdb
the above is the wrong md0 using whole disks

this one is the correct one
> ARRAY /dev/md0 level=raid5 num-devices=4 
> UUID=08558923:881d9efd:464c249d:988d2ec6
>    devices=/dev/sde1,/dev/sdd1,/dev/sdc1,/dev/sdb1
>
> root at adam-desktop:~# mdadm --examine --verbose /dev/sdb
> root at adam-desktop:~# mdadm --examine --verbose /dev/sdc
> root at adam-desktop:~# mdadm --examine --verbose /dev/sdd
> root at adam-desktop:~# mdadm --examine --verbose /dev/sde

you did not dump the partitions, but i guess you couldn't since the
device files disappeared

> root at adam-desktop:~# cat /proc/mdstat
> Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] 
> [raid4] [raid10]
> md0 : active raid5 sde[3] sdb[0] sdc[1] sdd[2]
>       2930287488 blocks level 5, 64k chunk, algorithm 2 [4/4] [UUUU]
>
> unused devices: <none>
>

put 
DEVICE /dev/sd?1
ARRAY /dev/md0 level=raid5 num-devices=4 UUID=08558923:881d9efd:464c249d:988d2ec6

into /etc/mdadm.conf (or /etc/mdadm/mdadm.conf, whatever ubuntu places
it) and reboot, you should be able to see your data.

after this ask on linux-raid ml for advice on how to zero the duplicate
superblock.

L.

-- 
Luca Berra -- bluca at comedia.it
         Communication Media & Services S.r.l.
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