[ovirt-users] disaster recovery

[Nathanaël Blanchet]

Hello all,

Here is what can happen as a nightmare for a sysadmin:

I installed a new host to my pool of pre existing ovirt hosts with a 
kickstart file and a default partitionning. I used to do this with vms 
that usually get one local disk.
But..
This time this host was attached to several existing ovirt (production) 
lun and anaconda gathered all existing disk (local and lun) into the 
same VG (lv_home) et formatted them with XFS....
In the webadmin, the domain storage became unvailaible, vms were still 
up (thankgoodness), but it was impossible to interact with them. If I 
stopped them, it was impossible to reboot them. If I launch lvs command, 
some hosts can still see the ovirt LV, but other see only the lv_home 
while /dev/[idofvms] are still present.
So it was my chance that vms were still present, and I began to export 
them with a tar at file system level so as to import them in a new 
domain storage.

It seems that data are still present because the vms are still running.
So my question is really : instead of this difficult export step, is 
there a way to recover the initial format of the ovirt lun so as to make 
the lvm index come back on the disk?

Any help or disaster experience would be much appreciated.

-- 
Nathanaël Blanchet

Supervision réseau
Pôle Infrastrutures Informatiques
227 avenue Professeur-Jean-Louis-Viala
34193 MONTPELLIER CEDEX 5 	
Tél. 33 (0)4 67 54 84 55
Fax  33 (0)4 67 54 84 14
blanchet at abes.fr