Abstract: A cluster of computer system nodes share direct read/write access to storage devices via a storage area network connected to the nodes by switches, such as Fibre Channel switches. When a node fails to respond to other members of a cluster, the node is prevented from accessing storage devices shared by the nodes in the cluster by disabling port(s) on the switches connected to the failed node. The ports to be disabled are identified in a cluster configuration database that is updated as each node joins the cluster. Commands to disable port(s) of a switch may be transmitted to the switch in a telnet session from the node maintaining the cluster configuration database.