To restrict disclosure of a plurality of logical volumes corresponding to a plurality of logical units composing a copy pair to applications.

A storage access device, which issues an I/O request (input/output request) to logical units provided by one or more storage systems, holds association information indicating that a plurality of logical volumes corresponding to a plurality of logical units belonging to the same copy set are associated. In the storage access device, each of the associated logical volumes indicated by the association information is allocated to a virtual device, and the virtual device is disclosed to an application.