VOVA, which is based on the OpenStack Havana release, lets administrators take empty vSphere clusters and use the OpenStack Web GUI or a vSphere command-line interface (CLI) to create virtual machines (VMs), which Vmware calls instances.
The administrator needs to prepare the clusters before implementing VOVA and also adjust settings, including those for the Distributed Resource Scheduler (DRS), shared storage and ESX firewall. VMware recommends using vCenter 5.1 and higher to run VOVA.
VOVA is a proof-of-concept appliance, suitable for testing and educational purposes. VMware does not offer technical support for VOVA nor does it recommend VOVA for production environments.
See also: VMware fling