1. A method for controlling access to a shared storage system wherein the shared storage system is in communication with at least one cluster of host nodes, comprising: storing cluster membership metadata in a metadata store independent from the shared storage system for the at least one cluster and a membership controlling component in a storage controller mediating access to the shared storage system; updating the cluster membership metadata in response to an inclusion or exclusion request from a requesting host node comprising one of the host nodes identifying at least one host node to include or exclude from a cluster, wherein the shared storage system includes the storage controller and at least one storage volume; managing, by the membership controlling component, access to at least one storage volume in the shared storage system in response to the updating of the cluster membership metadata for the inclusion or exclusion request; resolving, by a resolution component, a conflict of the inclusion or exclusion request to the cluster membership metadata with previous messages using a quorum tie-breaking function; and rejecting the inclusion or exclusion request in response to determining that the inclusion or exclusion request conflicts with the previous messages.