Storage system

There is provided a technique in which such a configuration as to include storage apparatuses on a plurality of sites can reduce a burden of operation/management of backup of data stored in the storage apparatuses. The configuration includes a information processing system on each site to be a backup target, and an information processing system for executing a backup process. Through control of a management server and a process for a backup server at a backup execution point, backup data of the data stored in the storage apparatus of the information processing system is converged into the storage apparatuses of the information processing systems by a process using a remote copying function and stored in the backup device. Then, instructions are given from the management server to the respective sites with synchronized timing, and convergence and storage of said backup data are executed by obtaining a temporal synchronization.