Patent ID: 6993680

Claim:
A storage device comprising: a disk driving device for storing data that are received from an information processing apparatus; a cache memory for temporarily retaining data to be stored in the disk driving device; a backup power source for backing up individual units of the storage device including the disk driving device and the cache memory; a power failure detecting unit for checking a status of power supply from a power source; a backup power supply control unit for distributing output power of the backup power source to the individual units of the storage device including the disk driving device and the cache memory in a first period that starts after detection of a power failure by the power failure detecting unit, and for supplying the cache memory with power that has been distributed to units excluding the cache memory after a lapse of the first period; a data accepting unit for accepting data from the information processing apparatus and writing the accepted data to the cache memory; and a data transfer unit for transferring data stored in the cache memory to the disk driving device, wherein the power failure detecting unit is provided in each of the data accepting unit and the data transfer unit, and the power failure detecting units detect a power failure by checking statuses of power supply from the power source in the data accepting unit and the data transfer unit, respectively, and communicating check results to each other.