FDRABRCM PURGE BACKUP Statement

PURGE BACKUP statement syntax

PURGE BACKUP statement

PURGE BACKUP scans the ABR catalog for records of ABR backups that are obsolete and uncatalogs them.

For every DASD volume initialized for ABR processing, the ABR Model DSCB in its VTOC contains the maximum number of generations (MAXGEN) that your installation wants to keep for that volume; the generation number is incremented for every full-volume backup. PURGE BACKUP takes the current generation number for each volume, minus its MAXGEN value; any backups for that volume still cataloged in the ABR catalog with generation numbers prior to that are eligible for purge.

Therefore, with no other operands, PURGE BACKUP uncatalogs any ABR backups that are not within the range of generations that you have indicated to be kept for each DASD volume. Since normal ABR operation also uncatalog these obsolete backups, this processing is required only to clean up backup entries that were not automatically uncataloged for some reason. Most installations run PURGE BACKUP periodically (perhaps once a month).

Operands are available to override the MAXGEN value from the ABR Model DSCB, to limit the purge based on backup date, and to purge specific generations and/or cycles.

PURGE BACKUP Operands

Specifies that ABR backups that are outside the MAXGEN limits are uncataloged only if they were created on or before the Julian date (year plus day number) specified. The date may be in the form “yyyyddd” (for example, 2020123) or “yyddd” (for example, 20123). If the 2-digit year is used “yyddd”, year numbers less than 70 are assumed to be in the 21st century, for example, 20015=2020.015. For readability, a period may be inserted between the year and day (for example, 2020.123).

nnnn

Specifies that ABR backups that are outside the MAXGEN limits are uncataloged only if they were created on or before the date calculated by subtracting BKDAYS= from today's date.

If neither BKDATE= nor BKDAYS= is specified, ABR backups are uncataloged based only on the generation number (MAXGEN).

n

Specifies the copy number (1 or 2) you wish to uncatalog.

Default: Both copies are uncataloged.

Specifies one or more cycle numbers you wish to uncatalog. Only the specified cycles from within each generation selected are purged. You may specify CYCLE=ALL, which selects all cycles in every selected generation except for cycle 00 (the full-volume backup) in each generation and the most recent cycle in the current generation (the most recent backup).

Default: All cycles within selected generations, except the most recent cycle in the current generation (unless FORCE is also specified).

Specifies what source contains the correct current generation and cycle values when the ABR Model DSCB and ABR backup entries conflict.

The ABR backup entry with the highest backup date contains the most current information.

The ABR Model DSCB contains the correct values.

Default: MODEL, unless the DASD volume has no ABR Model DSCB, in which case CATLG is used; in this case the MAXGEN= operand is also required since this information is stored only in the ABR Model DSCB.

Specifies that no checks or limitations are applied when selecting backups for uncatalog. This is usually used to completely uncatalog all backups for a volume that no longer exists or is no longer being backed up by ABR. This operand also requires the use of the VOL= operand.

Specifies one or more generation numbers the user wishes to select for processing. This value can be any generation except the most current generation unless FORCE is also specified.

Lists only entries that were selected but not successfully purged (uncatalog error).

Default: If GEN= is not specified on the PURGE statement, are the entries found outside the MAXGEN limits for the volume.

Specifies a maximum number of generations to keep in the ABR backup catalog for each DASD volume. You may also code MAXGEN=DEFAULT which directs the program to use the ABR default from the FDR Global Options, which is normally four.

Default: Taken from the ABR Model DSCB in the VTOC of each DASD volume.

Specifies that only volume entries within the ABR backup catalog not having a corresponding ABR Model DSCB (missing from the VTOC or the volume is offline) are selected for processing.

Default: Only ABR backup entries having an ABR Model DSCB available are selected. When no model condition exists CURRINFO=CATLG is set by the program that also requires MAXGEN= operand to be specified.

If VOL= or VOLG= were specified, but one or more of the values specified for those operands did not match any entries in the ABR catalog, SELTERR= controls whether this causes FDRABRCM to end with a non-zero return code. Specify NO if you want the step to end normally even though there were some unmatched selection criteria.

Default: YES.

SIMULATE

Specifies that FDRABRCM is to report on all the ABR backup names selected, but is not to actually purge any. This is used to verify that your PURGE statement has the desired results.

Default: PURGE processing is attempted.

Specifies a DASD volume serial number (VOL=) or volume serial prefix (VOLG=). Backups of these volumes are considered for purge. Multiple volume serial numbers may be specified in parentheses separated by commas.

Default: If neither VOL= nor VOLG= is specified, entries are considered regardless of the DASD volume. Both VOL= and VOLG= may be specified on the same PURGE statement; each backup is compared to the combined list.