OpenNebula combines existing virtualization technologies with advanced features for multi-tenancy, automated provisioning and elasticity. A built-in virtual network manager maps virtual networks to physical networks. OpenNebula is vendor neutral, as well as platform- and API-agnostic. It can use KVM, Xen or VMware hypervisors.
OpenNebula, which now operates as an open source project, began as a research project by Ignacio M. Llorente and Rubén S. Montero in 2005. The first public release of OpenNebula was in March 2008.