Abstract: An apparatus and method for a computer system is used for implementing an extended distributed recovery block fault tolerance scheme. The computer system includes a supervisory node, an active node and a standby node. Each of the nodes has a primary routine, an alternate routine and an acceptance test for testing the output of the routines. Each node also includes a device driver, a monitor and a node manager for determining the operational configuration of the node as well as a common agent, the common agent being a hybrid software agent comprising both the characteristics of an EDRB model and a virtual circuit state machine, wherein the attachment objects of the agent are identical regardless of where instances of the agent are located. The supervisory node acts as an arbitrator and coordinates the operation of the active and standby nodes. A reliable data link extends between the monitors of the active and standby nodes.