To install Oracle VM, you must install at least one Oracle VM Server and one instance of Oracle VM Manager. Your Oracle VM Server can be on either x86 hardware or SPARC hardware. Oracle VM Servers in a server pool must be of the same type, either x86 or SPARC. You cannot mix x86 and SPARC servers in the same server pool; however Oracle VM Manager can manage server pools of different types.
If you are planning to install Oracle VM in a production environments, the following requirements apply:
Oracle VM Manager and Oracle VM Server versions should be the same. You can use Oracle VM Manager to manage an Oracle VM Server within the same release but at a different patch level. However, it is recommended that you maintain the same patch level for both Oracle VM Manager and Oracle VM Server.
A minimum cluster of three Oracle VM Server nodes in each server pool is strongly recommended for high availability (HA). If one node in the cluster experiences a hardware failure or is shut down for maintenance, failover redundancy is preserved with the other two nodes. Having a third node in the cluster also provides reserve capacity for production load requirements.