See definition for: Preboot Execution Environment quorum disk The cluster disk on which configuration data is maintained in the quorum log, cluster database checkpoint, and resource checkpoints. The quorum disk is managed by the Quorum resource, which is usually a special kind of Physical Disk resource. Remote Installation Services (RIS) Software services that allow an administrator to set up new client computers remotely, without having to visit each client. The target clients must support remote booting. See also: Preboot Execution Environment SAN See definition for: storage area network (SAN)