Detailed descriptions of these software products are provided in the “HSMS” [13] and “ARCHIVE” [3] manuals.
The MAREN catalog is the central administration point for all tapes, including the backup tapes used by HSMS and ARCHIVE in a data center. The information on the backup tapes contained in the MAREN catalog must always accurately reflect the actual status. HSMS and ARCHIVE manage the information on the backups created and their tapes in archive directories, which are referred to as directories.
The information in the MAREN catalog must always be consistent with the information in all directories. I.e. an archive number should not be identified as being “free” in the MAREN catalog but still contained in a directory.
HSMS/ARCHIVE and MAREN consequently have internal interfaces for exchanging information. To guarantee the MAREN catalog and the directories remain consistent, when HSMS/ARCHIVE and MAREN are used, the BS2000 system administration must ensure that MAREN is always loaded and operational.
Administration of the archive numbers is facilitated by the cooperation of MAREN and HSMS/ARCHIVE. An archive number which is added to a directory needs no MAREN statement, as the MAREN catalog is automatically updated correspondingly.
The MAREN administrator can assign specific HSMS/ARCHIVE applications, specific archive numbers or archive number ranges. For instance, this always enables the save operation to be executed on a specific set of tapes.
When automatic free tape allocation is used in MAREN, manual entry of an archive number is not required. This is achieved under HSMS with the VOLUMES=*FROM-OPERATOR operand, and under ARCHIVE with the TAPES=OPERATOR operand of the backup statements concerned. The MAREN catalog and directories are then updated automatically.
Administration of the tapes is largely identical in HSMS and ARCHIVE. This also applies for the interfaces to MAREN, and is evident in some terms. For instance, no distinction is made between HSMS and ARCHIVE in the MAREN free tape pools. In MAREN, only the term ARCHIVE free tape pool exists, although corresponding usage by HSMS is meant. From MAREN’s viewpoint, no distinction is made between HSMS and ARCHIVE.
Furthermore, the mechanisms presented here are not restricted to the backup functions of HSMS and ARCHIVE, but also apply analogously for data migration under HSMS to storage level S2. However, for simplicity’s sake, only backup is referred to below. Backup files (comparable with the normal data backup) are also written to tape in the case of data migration. No distinction exists from MAREN’s point of view.
In MAREN, free tapes can be prereserved for HSMS/ARCHIVE applications by assigning them to a HSMS/ARCHIVE free tape pool. This prereservation of free HSMS/ARCHIVE tapes within the MAREN free tape pool is implemented for specific directory names or globally for HSMS/ARCHIVE applications, and is the responsibility of the MAREN administrator.
This allows the data center to supply the normal save runs (e.g. daily, weekly or monthly save runs) with the correct tapes and permanently defined directories. User save systems with their own directories can use the above mechanism or access any number of tapes from the global MAREN free tape pool for HSMS/ARCHIVE.