Patent ID: 7787388

Claim:
A fault-tolerant, two-node system for performing a service in a manner that autonomously isolates and disables a failing node from disrupting said service, the system comprising: a first and a second node, each including a communication fabric interface; a fault-tolerant communication fabric having a plurality of switch structures and links, said fabric defining a plurality of communication paths connecting the communication fabric interfaces of the first node and the second node, said fabric providing fault-tolerant loop-back communication in which said first node can send a message to itself utilizing at least one switch structure of said fabric, and in which said second node can send a message to itself utilizing at least one switch structure of said fabric; and wherein each of the two nodes includes logic for performing said service in accordance with a service delivery model, logic for testing the functionality of the respective node to determine whether the respective node is capable of successfully performing said service, logic, responsive to said testing logic, for sending test result messages to the respective node using loop-back communication provided by said fault-tolerant fabric and for sending test result messages to the other node using a communication path defined by said fault-tolerant fabric, fault-isolation logic for analyzing test result messages from the respective node and from the other node to determine whether the respective node or the other node is capable of successfully performing said service; and logic for disabling the other node from performing said service only if the fault-isolation logic determines that the respective node is capable of successfully performing said service and also determines that the other node is incapable of successfully performing said service, said system including logic, responsive to said logic for disabling, for continuing delivery of said service in accordance with said service delivery model.