In a data processing system Saving a primary site and a secondary site,
storage systems are connected to each other via a communication line,
data update history is recorded in a storage device as a journal in the
primary site, and the journal is transferred to the secondary site via
the communication line. During such transfer, loads will not concentrate
to a specific volume, by switching the volume that stores the journal in
the primary site, while, by switching the transfer-destination volume of
the journal in the secondary site.With such arrangement, in a data
processing system, it is possible to ensure data consistency in a
plurality of sites and prevent the system throughput capacity from being
deteriorated without applying loads to a host and a network, and without
causing load concentration on a specific storage device that is caused as
a result of data update or recovery operations.