Patent ID: 7536522
Filing Date: 2009-05-19
Classification: G06F

Abstract:
1. A computer system, comprising: at least one first storage system; at least one second storage system connected to the first storage system; a host computer; and a management computer which manages the first storage system and the second storage system, wherein the first storage system comprises a first interface for connecting with the second storage system, a first processor connected to the first interface, and a real storage area for storing data that is requested to be written in a virtual storage area set in the second storage system, wherein the second storage system comprises a second interface for connecting with the host computer and the first storage system, a second processor connected to the second interface, and a second memory connected to the second processor to provide the host computer with the virtual storage area in which data is written, wherein the virtual storage area is associated with the real storage area, wherein, when the real storage area is allocated to the virtual storage area, the real storage area stores data that is requested to be written in the allocated virtual storage area, wherein the management computer comprises a third interface connected to the first storage system and the second storage system, a third processor connected to the third interface and a third memory connected to the third processor, and wherein, upon receiving a copy request that designates the real storage area as a copy source real storage area, the third processor: selects one virtual storage area that is associated with plural real storage areas as a copy destination virtual storage area; upon judging that the copy source real storage area is not allocated to a copy source virtual storage area but is associated with the copy source virtual storage area, switches copy source allocation from one real storage area to the copy source real storage area, and switches copy destination allocation from one real storage area to another real storage area associated with the copy destination virtual storage area, in accordance with the copy source allocation switching; instructs, based on a result of the judging, to copy data that is stored in the copy source real storage area to a copy destination real storage area, stores, in the third memory, copy pair information about a replication relation between the copy source real storage area and the copy destination real storage area on which the data copy has been performed.