One or more storage systems are connected to one or more storage boxes comprising multiple storage devices. Multiple storage areas provided by one or more storage boxes include an allocated area, which is a storage area that is allocated to a virtual volume, and an empty area, which is a storage area that is not allocated to any logical volume. Multiple owner rights corresponding to multiple storage areas are set in one or more storage systems. A storage system having an empty area owner right changes an empty area to the allocated area by allocating the empty area. In a case where a configuration change (a relative change in the number of storage boxes with respect to the number of storage systems) is performed, a first storage system that exists after the configuration change sets, in the first storage system, either more or fewer owner rights than the owner rights, which have been allocated to the first storage system before the configuration change.