Storage system and operation method thereof

An operation method of a storage system having a function to back up data stored in a storage area, the storage system including a storage device that includes a storage medium providing the storage area;

• a magnetic tape device that includes a magnetic tape providing a storage area, which is a write destination, where the data stored in the storage area of the storage device is to be backed up;
• and a control unit that performs writing and reading processings of the data between the storage device and the magnetic tape device, the method comprising:
• receiving backup type information, which is information indicating a backup type when backing up the data to the magnetic tape;
• acquiring tape position information recording interval information corresponding to the backup type information thus received, from the tape position information recording interval information which is held in association with the backup type information thus received and which indicates a recording interval of tape position information on the magnetic tape, the tape position information being positional information recorded on the magnetic tape to associate a data storing location in the storage medium and a recording location of the data on the magnetic tape with each other;
• and
• transmitting, to the control unit, the tape position information recording interval information thus acquired,
• wherein each step is performed by a tape position information recording interval managing unit coupled to the storage device and the magnetic tape device.