Mapping management information denoting the mapping of a first host and first host volume and a second host and second host volume is prepared beforehand. First-path-redundancy information, which is related to the redundancy of a first path of the first host volume, is acquired, and a second host volume and second host mapped to this first host volume and the first host thereof are specified by referencing the mapping management information. The redundancy of a second path, which links the specified second host volume and a second storage volume, is decided based on the first-path-redundancy information. Second-path-redundancy information, which is related to the decided second-path redundancy, is outputted to configure the decided second-path redundancy in the above-mentioned specified second host.