Patent ID: 8103754

Claim:
A method for reserving a shared volume in a data storage system, comprising: nodes of the data storage system each storing a reservation status of the shared volume, the shared volume being accessible by hosts via the nodes, the reservation status being unreserved when the shared volume is available for host access, the reservation status being reserved when the shared volume is unavailable for host access; a node in the data storage system receiving a request from a host to use the shared volume; in response to receiving the request, the node sending the request to a reservation system of the data storage system, the reservation system being located on one of the nodes of the data storage system; and in response to receiving the request, the reservation system reserving the shared volume for the host when the reservation status indicates that the shared volume is unreserved, wherein said reserving comprises the reservation system sending a reservation set request to the nodes to change the reservation status on the nodes.