1. A method comprising: detecting when a computer system cluster including at least one coordinator storage device is partitioned, wherein the computer system cluster is partitioned into a first subcluster comprising at least a first node and a second subcluster comprising at least a second node; identifying, for an attempt to unregister, the first node of the first subcluster; attempting to unregister a key associated with the first node on a majority of the at least one coordinator storage device, wherein the identifying and the attempting are performed by the second node; sending an unregister with resource command to a shared data resource in response to having unregistered said key on the majority of the at least one coordinator storage device; and removing at least the second node from the computer system cluster when the attempting is unsuccessful.