In order to construct an integrated storage system by reinforcing collaboration of components or functions of a storage system in which a storage area network (SAN) is used, in a computer system having multiple client computers, multiple various servers, multiple various storages which keep data, and a local area network (LAN) which connects the computers and the servers, a storage area network (SAN) which lies between the servers and storages forms a switched circuit network which is capable of connecting any server and any storage through fiber channel FC switches. The computer system further includes a terminal which is equipped with operation and management software which performs storage management including management of logical volumes in the various storages, data arrangement, error monitoring, management of setting up the FC switches, and backup for data in the storages.