Patent ID: 7657768

Claim:
A system comprising: a disk array apparatus including first disk devices configuring a first logical unit and second disk devices configuring a second logical unit and a controller coupled to the first disk devices and the second disk devices; and a computer coupled to the disk array apparatus, wherein in response to a first instruction from the computer, the controller starts to copy data from the first logical unit to the second logical unit, wherein when the computer issues the first instruction to the disk array apparatus, the computer issues a second instruction to request the controller to turn on the second disk devices configuring the second logical unit, so that in response to the second instruction, the controller turns on the second disk devices before the controller starts to copy data from the first logical unit to the second logical unit, wherein the computer issues a third instruction to the disk array apparatus to request the controller to stop data copying from the first logical unit to the second logical unit, wherein after the computer receives a report of stop of the data copying from the first logical unit to the second logical unit, the computer issues a fourth instruction to the disk array apparatus to request the controller to turn off the second disk devices, and wherein the controller turns off the second disk devices in response to the fourth instruction.