Cluster resource action in clustered computer system incorporation prepare operation

Abstract

An apparatus, clustered computer system, program product and method utilize a unique prepare operation in connection with a resource action to effectively 'lock out' missing or inactive cluster entities such as nodes and cluster objects from rejoining a clustered computer system subsequent to the resource action. The prepare operation includes the modification of one or more cluster configuration parameters associated with a plurality of entities in a clustered computer system, such that any such cluster entity that is active during the prepare operation accepts the modifications, while any such cluster entity that is inactive during the prepare operation does not accept the modifications. By modifying cluster configuration parameters for active cluster entities, attempts by previously-inactive cluster entities to activate or rejoin clustering subsequent to resource actions will generally fail due to an incorrect or stale cluster configuration parameters for such entities, and as a result, such entities will be effectively blocked from being accepted into the clustered computer system.