The oVirt Server is an open cross-platform virtualization management
system. It provides a web-based management interface that enables
users to manage hosts and storage, install and remove virtual machines
and level resources across a large group of machines. The oVirt Server
manages hosts running the oVirt Node Image. oVirt Server Suite scales
from a small group of users with little need for access control and
quota management, all the way up to hundreds of hosts with robust
control over grouping, permissions, and quotas.

For further docs see: http://ovirt.org