When performing asynchronous remote copying, whether or not a disaster has occurred at a main site is judged at a remote site; and if the disaster has occurred, recovery processing is immediately started at the remote site. When asynchronous remote copying is performed between a controller and a controller, the controller transfers remote copy target data in a storage apparatus and command information via a remote copy channel to the controller; and after receiving the remote copy target data, the controller stores the remote copy target data in a storage apparatus; and if the controller fails to receive the command information within a set time period, the controller judges that a disaster has occurred, and then outputs the judgment result to a backup center server; and the backup center server executes recovery processing based on data in the storage apparatus when the disaster has occurred.