Patent ID: 8732420

Claim:
A remote copy system comprising: a first storage system managing a first logical volume as a primary logical volume for a synchronous copy pair, a second storage system managing a virtual volume as a secondary logical volume for the synchronous copy pair and a primary logical volume for an asynchronous copy pair, and a third storage system managing a second logical volume as a secondary logical volume for the asynchronous copy pair and storing a copy of data, wherein, if the remote copy system receives a command for changing a state of an asynchronous copy using the asynchronous copy pair to a state for copying while a state of a synchronous copy using the synchronous copy pair is in the state for copying, the remote copy system rejects the command, and wherein, if the remote copy system receives a command for changing a state of an asynchronous copy using the asynchronous copy pair to a state for copying while a state of a synchronous copy using the synchronous copy pair is not in the state for copying the remote copy system does not reject the command.