Patent ID: 7774469

Claim:
A computer-implemented method, comprising: maintaining operational data of a cluster on a replica set comprising a plurality of replica members that includes at least one independent replica member that is a device that is not integral to any node of the cluster and wherein the at least one independent replica member is configured to be online in the replica set regardless of how many of the any nodes are operable in the cluster and wherein each of the replica members can be controlled by only one of the any nodes at a time and wherein each of the replica members is a device configured to maintain a replica of the operational data of the cluster; maintaining an epoch number in association with each replica member, wherein a value of each epoch number indicates a relative state of the cluster operational data on its respective replica member, and wherein at least two replica members have epoch numbers that equal a largest epoch number; maintaining a sequence number in association with each replica member; representing the cluster if a number of replica members exclusively owned and controlled by the only one of the any nodes comprises at least a majority of a total number of replica members of the replica set; determining which of the replica members has operational data that is most updated, wherein the determining includes determining that the at least two replica members have epoch numbers that equal the largest epoch number and determining which of the at least two replica members have a sequence number that equals a largest sequence number; and replicating at least some of that operational data by the only one of the any nodes to the other replica members of the replica set wherein others of the any nodes access the operational data of the cluster only through the only one of the any nodes.