In June, the oVirt Project shipped version 4.0 of its open source virtualization management system. With a new release comes an update to this howto for running oVirt together with Gluster storage using a trio of servers to provide for the system's virtualization and storage needs, in a configuration that allows you to take one of the three hosts down at a time without disrupting your running VMs.
One of the biggest new elements in this version of the howto is the introduction of gdeploy, an Ansible based deployment tool that was initially written to install GlusterFS clusters, but that's grown to take on a bunch of complementary tasks. For this process, it'll save us a bunch of typing and speed things up significantly.
Important Note: I want to stress that while Red Hat has recently begun to sell and support a converged virtualization and storage configuration on a limited basis, the converged oVirt/Gluster setup I describe here should be considered somewhat bleeding edge.
If you're looking instead for a simpler, single-machine option for trying out oVirt, your best bet is the oVirt Live ISO. This is a LiveCD image that you can burn onto a blank CD or copy onto a USB stick to boot from and run oVirt. This is probably the fastest way to get up and running, but once you're up, this is definitely a low-performance option, and not suitable for extended use or expansion.