Patent ID: 7653792

Claim:
A disk array apparatus, comprising: first storage devices, which are high speed devices, having a plurality of first storage areas; second storage devices, which are low speed devices relative to the high speed devices, having a plurality of second storage areas; and a controller which is arranged to be coupled to a host computer and which controls a read/write operation of data to or from one of the first storage areas in response to a read/write command issued from the host computer; wherein the controller includes information relating to an access authority to each of the first storage areas, said information being used when a read/write command is received for reading/writing data stored in said first storage areas, and said information being changed in response to a command received by said disk array apparatus to change an access authority; wherein the controller executes control to move data from one of the first storage areas to one of the second storage areas in response to an access authority change command received from the host computer inhibiting an access authority of the host computer to the first storage area from which the data is moved; wherein the controller executes control to move data from one of the second storage areas to one of the first storage areas in response to an access authority change command received from the host computer releasing said inhibiting of an access authority of the host computer to said one of the first storage areas to which the data is moved.