Patent ID: 7467273

Claim:
A computer system comprising: a first storage system; a second storage system connected to said first storage system; a first storage area which is a plurality of storage areas in said first storage system; and a second storage area which is a plurality of storage areas in said second storage system, wherein said first storage system comprises: a controller unit for providing said second storage area as a storage area of said first storage system to a first computer connected to said first storage system; and an access control command unit for commanding said second storage system to restrict the access to a prescribed storage area in said second storage area from a second computer connected to said second storage system, and wherein said second storage system comprises: an access control configuration unit for restricting the access to said prescribed storage area in said second storage area from said second computer based on a command of said access control received from said access control command unit of said first storage system, wherein said controller unit comprises: a first I/O processing unit for controlling an I/O request to said first storage area from said first computer; and a second I/O processing unit for providing said second storage area as a storage area of said first storage system to said first computer via said first I/O processing unit, and for controlling an I/O wherein said controller unit comprises: a first I/O processing unit for controlling an I/O request to said first storage area from said first computer; and a second I/O processing unit for providing said second storage area as a storage area of said first storage system to said first computer via said first I/O processing unit, and for controlling an I/O request to said second storage area via said first I/O processing unit, and wherein said access control configuration unit prohibits a write request from said second computer to data stored in said prescribed storage area in said second storage area based on a command of said access control received from said access control command unit of said first storage systemequest to said second storage area via said first I/O processing unit, and wherein said access control configuration unit prohibits a write request from said second computer to data stored in said prescribed storage area in said second storage area based on a command of said access control received from said access control command unit of said first storage system.