Patent ID: 7117340

Claim:
A storage system comprising: a first disk array system, in a primary site, coupled to a first host computer, comprising: a plurality of first disk drives, a first volume configured by some of said first disk drives, and a first controller storing data sent from said first host computer in said first volume and transferring copy data of said data sent from said first host computer with a remote copy procedure; and a second disk array system, in a remote site, coupled to said first disk array system and a second host computer, comprising: a plurality of second disk drives, a second volume configured by some of said second disk drives, and a second controller receiving said copy data from said first disk array system with said remote copy procedure and storing said copy data in said second volume, wherein said second volume is related to a first Logical Unit Number (LUN), which is used to access said second volume by said second host computer, and a second LUN, which is used for transferring said copy data from said first disk array system to said second volume with said remote copy procedure.