[ClusterLabs] snapshoting of running VirtualDomain resources - OCFS2 ?

[Lentes, Bernd]

Hi,

i have a 2-node-cluster with my services (web, db) running in VirtualDomain resources.
I have a SAN with cLVM, each guest lies in a dedicated logical volume with an ext3 fs.

Currently i'm thinking about snapshoting the guests to make a backup in the background. With cLVM that's not possible, you can't snapshot a lustered lv.
Using virsh and qemu-img i didn't find a way to do this without a shutdown of the guest, which i'd like to avoid.

I found that ocfs2 is able to make snapshots, oracle calls them reflinks.
So formatting the logical volumes for the guests with ocfs2 would give me the possibility to snapshot them.

I know that using ocfs2 for the lv's is oversized, but i didn't find another way to solve my problem.

What do you think ? I'd like to avoid to shutdown my guests, that's too risky. I experienced already several times that a shutdown can last very long
because of problems with umounting filesystems because of open files or user connected remotely (on windows guests).


Bernd

-- 

Bernd Lentes 
Systemadministration 
Institut für Entwicklungsgenetik 
Gebäude 35.34 - Raum 208 
HelmholtzZentrum münchen 
[ mailto:bernd.lentes at helmholtz-muenchen.de | bernd.lentes at helmholtz-muenchen.de ] 
phone: +49 89 3187 1241 
fax: +49 89 3187 2294 
[ http://www.helmholtz-muenchen.de/idg | http://www.helmholtz-muenchen.de/idg ] 

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