Dne 1.9.2014 v 20:13 Timur Alperovich napsal(a):
Hi there, I'm using LVM 2.02.98 and encountered a metadata corruption issue. To recover from it, I attempted to perform the following steps: 1. thin_check /dev/mapper/pool_tmeta 2. thin_dump /dev/mapper/pool_tmeta > /tmp/metadata
Hi NEVER EVER use _tmeta device from running active thin-pool volume. It's the very same case like you would be running 'fsck' on a mounted filesystem.
3. dd if=/dev/zero of=/dev/mapper/pool_tmeta 4. thin_restore -i /tmp/metadata -o /dev/mapper/pool_tmeta All of the above steps have succeeded, however, when attempting to list the _metadata\_percent_ field, I get an error:
I'm surprised you've not got kernel OOPS after such brutal destruction of life metadata device (i.e. almost equal to zeroing your root volume).
Is this a known issue and is there a workaround? I need to be able to examine the _metadata\_percent_ field to make sure we don't exhaust the metadata space.
Normal way - lvconvert --repair vg/pool If this is not working - then you can 'swap' metadata out of your thin-pool using following sequence- - make sure pool is not active. - build temporary local LV (lvcreate -l1 vg -n temp) - swap this LV with metadata of to-be-repaired pool (lvconvert --thinpool vg/fixpool --poolmetadata temp) - activate 'temp' LV now with pool's metadata (lvchange -ay vg/temp) - repair metadata (you may need other 'bigger' volume to restore fixed metadata) (i.e. thin_restore -i /dev/vg/temp -o /dev/vg/biggertemp) - thin_check restored volume - thin_dump - and compare vgcfgrestore & this dump are at the same transaction_id state (look at lvm2 metadata for thin pool) - deactivate again related volumes - swap repaired LV back (lvconvert --thinpool vg/fixpool --poolmetadata repairedtemp) - try to active repaired thin pool - remove unneeded volumes from vg.... Zdenek _______________________________________________ linux-lvm mailing list linux-lvm@redhat.com https://www.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
