A clustering storage system, which enables to operate a plurality of storage
system
units as a single storage system, presents connection information between clustering
storage systems to a user and receives data to be backed up and an instruction
about a path between the clustering storage systems from the user. The clustering
storage system uses load information or a transfer speed of a data connection line
between the storage system units to determine a path between the clustering storage
systems used for backup and a storage system unit for holding a backup copy so
that the data transfer between the storage system units becomes minimum. Besides,
the clustering storage system mainly uses the determined path for backing up the data.
