The object is to achieve a disaster recovery configuration in a short period of time. In a first storage apparatus 1P, a child-generation volume 3PB is created using a snapshot from a parent volume 3PA, and a grandchild-generation volume 3PC is created using a snapshot from the child-generation volume 3PB. Similarly, in a second storage apparatus 1S as well, a child-generation volume 3SB is created using a snapshot from a parent volume 3SA, and a grandchild-generation volume 3SC is created using a snapshot from the child-generation volume 3SB. The parent volumes form a normal remote copy pair. The child-generation volumes and the grandchild-generation volumes form virtual remote copy pairs without implementing an initial copy.