According to the present invention, unauthorized recording area information includes an optical disk having an unauthorized recording area that lacks data as one of a plurality of optical disks constituting a disk array, and a location in which the unauthorized recording area is present on the optical disk. A controller (110) includes: a recording control unit (121) for recording data in a distributed manner in a plurality of data blocks of the plurality of optical disks, and recording, in at least one parity block, at least one piece of parity data designed to restore the data in a data block that lacks data from among a plurality of data blocks; and a management information update unit (125) for recording the unauthorized recording area information in the management information area of at least one optical disk when data is lacking in at least one optical disk drive at data recording time.