I am in the process of deploying a two-node CentOS+Xen with iSCSI for live migration. The idea is to create a 600GB iSCSI lun, mount it on one of the servers and partition it with LVM. Each VM will have its own logical volume in the lun. I will do a vhchange -a y on the other server to activate the logical volumes. The question is: Am I going to need a clustered file system? (GFS2,OCFS) or its going to be fine? ALso, in case I add 2-3 more servers will this deployment still work or there is no way of doing it without a clustered file system? In each logical volume only one vm will write at the time and it will switch to another server only when it will migrate. I want to keep it as simple as possible, no RHCS or any other similar solution.