Storage apparatus having a virtual storage area

A storage apparatus which is provided between a tape storage apparatus and a host computer, the tape storage apparatus having a plurality of real tape volumes in at least one tape storage media and a driving mechanism, the host computer storing data exchanged between the host computer and tape storage apparatus in the storage apparatus as virtual tape volume, the storage apparatus comprising:

• a virtual storage area for storing at least one virtual tape volume group having at least one virtual tape volume, information of said virtual tape volume group being formed in a virtual tape information database, said database storing information about at least one attribute of each of said virtual tape volumes based on use of each of said virtual tape volumes;
• data transfer control means for controlling transfer of data among said virtual storage area, the host computer and the tape storage apparatus;
• a virtual special tape volume for collecting and recording the information about said at least one attribute of all virtual tape volumes;
• and
• means for reflecting changed contents of the virtual special tape volume edited by the host computer with respect to the information about attributes of said virtual tape volume stored in said database when the virtual special tape volume is mounted to the tape storage apparatus,
• wherein said data transfer control means forms groups of said virtual tape volumes having at least one common said attribute, and identifies said virtual tape volumes included in a selected said virtual tape volume group when the host computer issues a command to any one of the volumes of the virtual storage area.