In an information processing system including a central processor for
generating commands to process storage data stored and for executing a
sequence processing and a storage subsystem including a plurality of
storage media for transferring data between the plural storage media
according to commands from the central processor, a data recovery method
recovers data to a predetermined state upon occurrence of a failure in a
sequence of processing executed by the central processor. Before
execution of a sequence of processing, the central processor issues to
the storage subsystem a saving request to save in the plural storage
media a copy of data stored in either one of the storage media used in
the sequence of processing. In response to the saving request, the
storage subsystem saves a copy of data of the storage media.