The archiving programs ARCHIVE and HSMS, used in regular save operations, create backup copies of the current files.
The user can define a “backup level” for each of his files with the aid of the operand of the same name in the CATAL macro or CREATE-FILE and MODIFY-FILE-ATTRIBUTES commands.
Backup level “A”, for example, is the highest level and means that the file is saved with each save operation. Backup level “E”, in contrast, means that the file is saved when the maximum backup class "E" is set in HSMS/ARCHIVE.
Whether or not the selected backup level (A/.../E) affects the frequency with which the file is saved depends on the backup procedures used in the computer center.
If the computer center executes partial save runs, the user can also specify the scope of the partial save for his/her files: Using the CATAL macro (LARGE operand) or the CREATE-FILE and MODIFY-FILE-ATTRIBUTES commands (SAVED-PAGES operand), he/she specifies whether the complete file is to be saved in a partial save operation or – advisable for large files – a partial backup is sufficient.
The user can prevent HSMS from displacing a file to the background level by setting the file attribute MIGRATE to INHIBITED or FORBIDDEN. The HSMS administrator can bypass the INHIBITED setting, but not the FORBIDDEN setting.
The user can specify a file to be part of the version backup by setting a value > 0 for the NUM-OF-BACKUP-VERS file attribute. If the value is 0, the file is not part of the version backup. The value specifies the maximum number of file versions to be saved in the version backup archive. Temporary files, files on private disk, files on tape and file generations are not supported by the version backup, i.e. for these files the value can only be 0.
The setting is specified in the CATAL macro (NUM_OF_BACKUP_VERS operand) or in the CREATE-FILE and MODIFY-FILE-ATTRIBUTES (NUM-OF-BACKUP-VERS operand) commands. If no value is specified, the value from the NUMBACK system parameter is taken over for all files that support version backup.
More detailed information on file backups can be found in the manuals “ARCHIVE” [9 (Related publications)] and „HSMS“ [10 (Related publications)]; macros and commands for setting file attributes for file backup are described in the manuals “DMS Macros” [1 (Related publications)] and “Commands” [3 (Related publications)].