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

[Adam Newham <adam@thenewhams.com>]

  Many thanks for the assistance. With the this I should be pointed me 
in the right direction. As this now looks like a RAID related versus LVM 
issue I'll continue this on the RAID message list. For those interested, 
the thread can be found here:

http://marc.info/?l=linux-raid&m=128528502831454&w=2

Once again, thanks

On 09/23/2010 02:12 PM, Luca Berra wrote:
>> I also don't remember ever seeing /dev/md0p1 before, just a /dev/md0
> i guessed as much
>
>> root@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@adam-desktop:~# mdadm --examine --verbose /dev/sdb
>> root@adam-desktop:~# mdadm --examine --verbose /dev/sdc
>> root@adam-desktop:~# mdadm --examine --verbose /dev/sdd
>> root@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@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.
>