Patent attributes
Systems for managing shared entities between computing clusters while avoiding race conditions. Multiple clusters are interconnected over a network. When a node of a cluster intends to move a shared data item or virtual machine from its cluster to another cluster, the movement or migration can be initiated by establishing sole ownership followed by a request to an arbiter to intermediate during the movement or migration. The request explicitly includes subject entity metadata that describes sharing states pertaining to the subject entity. Upon granting a request, the arbiter generates a master copy of the entity metadata and grants itself read-write access. Any other sharers of the subject entity observe read-only access while the arbiter maintains the sole master copy. A sharer of the subject entity can cause changes to the subject entity through the arbiter. The arbiter can pass ownership to a new cluster to complete the subject entity migration.