Cloudstack/KVM using CLVM+ iSCSI for HA

[Douglas Land]

I'm part of a team setting up cloudstack right now. We're running KVM as our hypervisor and have set up iSCSI + CLVM for primary storage. We've run into an issue where it seems as though cloudstack doesn't recognize the CLVM partition as a shared device. It seems to treat it as a local filesystem (I guess because it's mounted locally?) and the VM won't fail over properly because cloudstack seems to think it's running on local only storage. We can manually bring the VM up on another host, but automated failover doesn't work. Has anyone seen this or had experience with this?  Thanks!

[Douglas Land]

Sorry, guess I got some of my facts wrong:

CLVM is not seen by Cloudstack as local storage. An LVM on CLVM formated as GFS or OCFS and mounted as shared mount on all nodes can be seen and used as local storage and local file system by Cloudstack but that would mean that VMs virtual disks are image files not logical volumes.

In our case where logical volumes are used on CLVM some mechanism for resource management is needed and it is RedHat's rgmanager but Cloudstack doesn't use it and doesn't consider it as well as Cloudstack does not have any similar own mechanism for management of logical volumes on CLVM.

So, CLVM is not local file system.