Method and apparatus for administering data on magnetic tape medium by way of a header segment

摘要

The control software and hardware in the tape drive control unit creates and manages a header segment at the beginning of the magnetic tape. This header is interposed between a leader portion of the magnetic tape on the 3480-type cartridge and the remainder of the magnetic tape contained therein. This header segment contains two sections, a first of which is a data record directory that is used by the control unit to denote the location of each data record written on to the magnetic tape as well as administrative information associated with the data record. The second section of the header is an administrative information section that contains data relating to the magnetic tape itself. The administrative information includes the identification of the tape volume, the tape drive, write protect status of the magnetic tape, identification of the media, error record log and other information that enables the user, the host processor and the tape drive control unit to manage the data records written onto the magnetic tape without reference to any other sources of administrative data. In addition, the header itself can be self protected by computing an error correction code across the data contained within the header to enable the control unit to identify whether the header integrity has been compromised.