1. A storage subsystem including: ports to which an interface for connecting a plurality of computers can be applied; logical unit accessible from said computers through said ports; one or a plurality of storage devices for storing data to be stored in said logical units; and a storage control device for controlling write/read of data to and from said storage device; wherein said computers gaining access to said logical units are grouped into groups with overlapping permitted; one or a plurality of said logical units is allocated to each of said groups; and a management table for associating said logical units allocated with storage areas of said storage devices with overlapping permitted is provided.