I'd like to begin using live migrations with my KVM install, but I do not have any shared storage. I will have 2 identical nodes, with their own local storage. Everything I've read seems to point to DRDB, but I am not finding many resources on how to implement DRDB + qcow2 + KVM. Currently I've been using virt-manager to manage my VMs which are all using qcow2 images. With a setup using DRDB, if I mount the replicated device to /var/lib/libvirt/images, what ensures that each virtual disk is only being used by a single node until migration is needed? I have no experience with HA systems or services.
What suggestions or experiences has anyone had with this type of setup? Any advice is welcome.