Patent ID: 7870426

Claim:
A system for cluster-wide peer recovery, the system comprising: a failed peer computer in a computer cluster; a plurality of peer computers in the computer cluster, the plurality of peer computers in communication with the failed peer computer, each peer computer comprising, a detection module configured to detect a failure of the failed peer computer; and a recovery module configured to register the corresponding peer computer as a counterpart of the failed peer computer, to block other peer computers from the plurality of peer computers from registering as the counterpart of the failed peer computer, to recover operation of the failed peer computer, and to unregister as the counterpart of the failed first peer computer responsive to detecting the failure of the failed peer computer, wherein the recovery module recovers the operation of the failed peer computer by initializing and starting the counterpart peer computer as the counterpart of the failed peer computer, retrieving private log data of the failed peer computer, backing out an in-flight transaction update of the failed peer computer by writing a before image derived from an undo log to files on a disk, and releasing a data resource locked by the failed peer computer; a recovery coordination module configured to accept and reject requests from the recovery module for registering as the counterpart of the failed peer computer, and unregistering the recovery module as the counterpart of the failed peer computer, a shared memory controller in communication with the failed peer computer and the plurality of peer computers, the shared memory controller configured to store and retrieve computer component status and log data, the shared memory controller further configured to prevent unauthorized access to private log data and to lock data resources; and a disk configured to store and retrieve user data and system data in the disk's storage media for the computer cluster.