Disk array apparatus and method for controlling the same

A disk array apparatus, comprising:

• a controller having a communication control unit for accepting a data input/output request, a disk controller unit for controlling a plurality of disk drives, and a cache memory for temporarily storing data transferred between said communication control unit and said disk controller unit;
• the plurality of disk drives being connected to the disk controller unit to communicate with the disk controller unit, the plurality of disk drives including a first disk drive;
• and
• a plurality of cooling fans cooling the plurality of disk drives, the plurality of cooling fans including a first cooling fan related to the first disk drive,
• wherein in response to receiving a backup request, the controller controls the rotational speed of the first cooling fan and changes an operational mode of the first disk drive related to the backup request such that the rotational speed of the first cooling fan is increased before the operational mode of the first disk drive is changed from a first mode of not storing data related to the backup request to a second mode of storing data related to the backup request.