LVM Disk fault and "unable to set superblock"

timmyx · 06-28-2011, 10:06 AM

Hi All,

Im trying to fix a disk which is inaccessible.

Its using LVM2

From a rescue disk I can scan and see the LVM device fine.

When I try to mount it fails.

When I run e2fsck it says "recovering journal" and then fails with "unable to set superblock flags"

I have tried running e2fsck -b 32768 (and other backup blocks) and it just says "recovering journal" and then fails with "unable to set superblock flags"

Can anyone help Please

Thanks

Karl Godt · 06-28-2011, 03:20 PM

Hello ! Not used to LVM , but what does

Code:

dumpe2fs /dev/THEDEVICE | head -n 60

show ?

tommylovell · 06-28-2011, 05:13 PM

Or, you could try Karl's suggestion using an alternate superblock.

Code:

dumpe2fs -h -o superblock=32768 -h /dev/mapper/<vg>-<lv>

Any idea why it's inaccessible?

timmyx · 06-28-2011, 05:34 PM

Hi All,

Thanks for the suggestions.

I managed to fix it by doing a low level copy of the disk onto another disk. It seemed to have no errors reading, it was just totally unable to write to it!

It was a SSD BTW (probably should have mentioned)

I used a program called ddrescue basically as such..

ddrescue -n /dev/hda /dev/hdb logfile
ddrescue -d -r3 /dev/hda /dev/hdb logfile
fdisk /dev/hdb
e2fsck -v -f /dev/hdb1
e2fsck -v -f /dev/hdb2

I could then boot from the 2nd (copied to) disk and all was good

syg00 · 06-28-2011, 06:09 PM

Good to hear - mark it as solved so others can see (thread tools at the top).