Patent ID: 7904684

Claim:
A system, comprising: source storage units; target storage units coupled to the source storage units; a storage control unit coupled to the source storage units and the target storage unit; means for performing copy operations on source storage units to copy to target storage units, wherein the copy operations create a consistent copy of the source storage units in the target storage units; and means for restricting a write operation from being performed on one source storage unit until the copy operations have been performed on the source storage units, while performing a copy operation to copy from the one source storage unit to one target storage unit, and wherein the system further comprises: (i) means for sending an establish copy command to the storage control unit; (ii) means for determining if there are additional establish copy commands to be sent to the storage control unit; and (iii) means for sending a copy consistency group command to the storage control unit, in response to determining that there are no additional establish copy commands to be sent to the storage control unit.