[linux-lvm] Shared VG, Separate LVs

[Eric Ren]

Hi,

> With CLVM / HA-LVM on a 2 node cluster -
>
> Is it possible to have a shared VG but separate LVs, with each LV 
> exclusively activated on different nodes in a 2 node cluster.
> In case of a failure, the LV of the failed node will be activated on 
> the other node.

I think clvm can do what you want if you perform LVM commands by hand. 
But, with HA cluster manager (pacemaker) you cannot
do it with the current resource agents (clvm + LVM) [1] [2], because 
they do failover at a VG basis.

We are currently working on new resource agents [3] for lvmlockd [4]. 
The new agents can do activation on LV basis, but I won't
recommend doing that if there's no strong reason. It makes things much 
more complicated.

[1] 
https://github.com/ClusterLabs/resource-agents/blob/master/heartbeat/clvm
[2] https://github.com/ClusterLabs/resource-agents/blob/master/heartbeat/LVM
[3] https://www.redhat.com/archives/linux-lvm/2017-January/msg00025.html
[4] https://github.com/ClusterLabs/resource-agents/pull/1040

Eric