I've been trying to figure out the best way of using an iSCSI SAN with KVM and thanks to a helpful post by Tom Georgoulias that I found on this list (https://www.redhat.com/archives/libvirt-users/2010-May/msg00008.html), it appears I have a solution.

What I'm wondering is the following:

1) If I use an iSCSI LUN as the storage pool (instead of creating an LVM VG from this iSCSI LUN manually first and using LVM in libvirt) do I loose any functionality (such as snapshotting)?

2) If I am intending on doing offline & live-migration between hosts, does each host have to connect to the same LUN / storage pool, or should each host have a separate LUN that is stores VMs on and then each host should simply see all of the LUNs so that migration is possible?

For example:

I create a LUN on the SAN, connect this to host 1 as a pool called "pool 1" and create VMs on it.

Then, on host 2, do I connect to the same "pool 1" and create VMs there, or do I just connect to "pool 1" in order to see it (for migrations) but also define "pool 2" from another new LUN on the SAN and create VMs there? Hope that makes sense..

I'm trying to understand in what situations I might get myself in trouble by two hosts performing storage operations at the same time on the same pool (which is unlikely, but I'm trying to figure out where I stand)

Thanks!

Anthony