Patent ID: 8578121

Claim:
A computer system, comprising: a plurality of storage apparatuses including at least a first storage apparatus with a first storage device and a second storage apparatus with a second storage device; and a plurality of management servers connected to each of the storage apparatuses via a management network for respectively managing each of the storage apparatuses, wherein the first storage apparatus is connected to one or more than two host computers as an access request source via a first communication network, and includes a first controller that is connected to the second storage apparatus via the first communication network or a second communication network, wherein the first controller manages one or more than two first virtual volumes with a virtual storage area as an access target of the access request source, assigns, a first internal logical volume configuring a logical storage area of the first storage device or an external logical volume associated with a second internal logical volume configuring a logical storage area of the second storage device, to any one of the first virtual volumes in response to an access request from the access request source, controls I/O processing of data to and from the first storage device upon access to the first internal logical volume, and controls I/O processing of data to and from the second storage device upon access to the external logical volume, wherein at least one management server among the plurality of management servers: determines existence or non-existence of abnormality of the first storage apparatus by sending and receiving information to and from the storage apparatus or the management server connected to the management network, and creates, when the first storage apparatus is subject to abnormality, a second virtual volume in the second storage apparatus as a normal storage apparatus among the storage apparatuses belonging to the plurality of storage apparatuses, and associates the second virtual volume in the second storage apparatus with the second internal logical volume in the second storage apparatus, which used to be assigned to the first storage apparatus as the external logical volume, based on configuration information shared between the first storage apparatus and the second storage apparatus, including a corresponding relationship between the first virtual volume and the internal and external logical volumes.