We've been having a really good experience using KVM / Libvirt on Scientific Linux, using QCOW2 format and virtio drivers for both Linux and Windows images. Once you get your base images registered in VCL, it is pretty straightforward to manage things in the normal VCL ways. When we need to poke around at the hypervisor level, using the virsh CLI via ssh works well, although you can also remotely run virt-manager to use a GUI ( virt-manager qemu+ssh://vmhost/system ). Simple bash scripts using virsh comands via ssh are very useful to automate housekeeping for a cluster of hypervisors, so it pays off to become familiar with virsh.
Peter Dimitrios
