The invention is a copy processing technique in a data processing system, which can simultaneously achieve long-distance communication and no data loss when disaster occurs. Among a production site, a local site, and a remote site, long-distance remote copying from a disk array device at the production site to a disk array device at the remote site without data loss is achieved via a disk array device at the local site in combination with synchronous remote copying and asynchronous remote copying. Also, in the disk array devices at the local site and the remote site, copying is performed through a replica function. Even if the production site is affected by disaster, tasks can be continued at the local site having the same data as that of the production site and at the remote site a long distance away from the production site.