[ClusterLabs] snapshots in a clvm environment - some questions for proceeding

[Lentes, Bernd]

Hi,

we have a two node cluster, our resources are several virtual machines running on kvm. The vm's reside in plain logical volumes, without a filesystem inside the lv's.
The lv's reside on a SAN.
I know that i can do a snapshot of a lv while having clvm when i acitivate it exclusively on one node. OK.
I tried it via lvchange -aly. I got "lvchange Using logical volume(s) on command line. lvchange    Activating logical volume "lv_cluster_01" locally". Seems to work.
Then i'm able to take the snapshot. But what is when i'd like to activate the lv cluster-wide again ? Is the snapshot gone or corrupted ?
I tried to activate it cluster-wide again with "lvchange -vay". Seems to work too.
Because, if i leave it exclusively activated on one note, i loose my high availibilty. How can it migrate to the other host if it is exclusively activated ?
How can i find out if a lv is activated exclusively ? How can i find out on which node it is activated exclusively ?

Thanks.


Bernd

-- 
Bernd Lentes 

Systemadministration 
institute of developmental genetics 
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bernd.lentes at helmholtz-muenchen.de 
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