Patent ID: 8281094

Claim:
A remote copy system comprising: a first storage subsystem located at a main site for sending/receiving information to/from a main site server; and a second storage subsystem located at a remote site for sending/receiving information to/from a backup center server; wherein the first storage subsystem includes a first storage apparatus for storing data and a first controller for controlling data input/output to/from the first storage apparatus; wherein the second storage subsystem includes a second storage apparatus for storing data from the first controller, a third storage apparatus for storing, as backup data, the data in the second storage apparatus, and a second controller for controlling data input/output to/from the second storage apparatus and transferring the data stored in the second storage apparatus, as the backup data, to the third storage apparatus; wherein when asynchronous remote copying is performed, the first controller transfers remote copy target data from among data in the first storage apparatus via a remote copy channel to the second controller and also transfers first command information including a heart-beat signal via the remote copy channel to the second controller; wherein when having received the remote copy target data via the remote copy channel, the second controller stores the received remote copy target data in the second storage apparatus; and when having received the first command information via the remote copy channel, the second controller transfers second command information, as information in response to the first command information, via the remote copy channel to the first controller; and if the second controller fails to receive the first command information within a set time period, it judges that a disaster has occurred, and then sends a judgment result to the backup center server; and wherein if the judgment result indicating the occurrence of the disaster is input from the second controller, the backup center server sends/receives information to/from the second controller and executes recovery processing.