US Patent 7380074 Selecting storage clusters to use to access storage

Provided are a method, system and program for selecting storage clusters to use to access storage. Input/Output (I/O) requests are transferred to a first storage cluster over a network to access storage. The storage may be additionally accessed via a second storage cluster over the network and both the first and second storage clusters are capable of accessing the storage. An unavailability of a first storage cluster is detected when the second storage cluster is available. A request is transmitted to hosts over the network to use the second storage cluster to access the storage. Hosts receiving the transmitted request send I/O requests to the storage via the second storage cluster if the second storage cluster is available.