Virtual tape apparatus, control method of virtual tape apparatus, and control section of electronic device

A control method of a virtual tape apparatus interposed between a host and a library device that makes an access to a physical tape volume so as to store data transmitted from the host to a logical tape volume, the method comprising:

• receiving data transmitted from the host;
• storing the data in a storage device having a logical tape volume;
• determining the write starting position of the data stored in the logical tape volume on the physical tape volume;
• and
• writing data in the logical tape volume to the physical tape volume based on a result of the determination, wherein
• the determining of the write starting position determines, out of data that have been written in the physical tape volume, data that has been invalidated and data to become invalidated through the current write processing based on attribute information of data that have been written in the physical tape volume and determines the next position of the endmost side valid data in the physical tape volume as the write starting position.

A control section of an electronic device connected to a library device that makes an access to a physical tape volume so as to store data stored therein in the physical tape volume, the control section comprising:

• a management table that retains attribute information of data stored in the physical tape volume;
• a write starting position determination section that determines the write starting position of the data stored in a storage device having a logical tape volume on the physical tape volume, the write starting position determination section determining, out of data that have been written in the physical tape volume, data that has been invalidated and data to become invalidated through the current write processing based on the attribute information retained in the management table and determining the next position of the endmost valid data in the physical tape volume as the write starting position;
• and
• a write processing section that writes data in the logical tape volume to the physical tape volume based on a result of the determination.