DUMPCLASS(VTOCCOPIES): Specifying the number of dump VTOC copy data sets to keep for dump copies created in this class

Explanation: VTOCCOPIES is an optional subparameter of DUMPCLASS specifying the number of dump VTOC data sets to keep for dump copies created in this class.

DUMPCLASS(VTOCCOPIES(copies)): For copies, substitute a number from 0 to 100. The value indicates how many of the existing dump copies of a given volume dumped to this class should have dump VTOC copy data sets kept associated with them. For example, use 3 as a value for copies. If there are six generations of dumps for a given volume and generations 0, 2, and 4 have copies in a class with VTOCCOPIES(3), then all of these generations have VTOC copy data sets kept for them. This happens regardless of what other dump copies might exist in the same dump generations, or whether generations 1, 3, and 5 have dump VTOC copies. If a new dump copy is created in the same class for the same volume, the oldest dump copy in this dump class no longer requires the dump VTOC copy data set. The dump VTOC copy data set is deleted if no other dump copy in the same generation requires it to be kept.

VTOCCOPIES is also used to determine if a dump VTOC copy data set should be created when a volume is dumped. If copies is greater than 0, a dump VTOC copy data set is created. If copies is 0 and the volume is not dumped to multiple dump classes concurrently, a dump VTOC copy data set is not created. If copies is 0 and the volume is dumped to multiple dump classes concurrently, a dump VTOC copy data set is created if any of the dump classes being dumped to has VTOCCOPIES(copies) greater than 0.

The dump VTOC copy data sets are written to migration level 1 volumes. Space required for these data sets varies with the size of the original VTOC. Only part of the data set VTOC entry for each data set from the original VTOC is contained in the VTOC copy data set. When a dump generation no longer has a dump VTOC copy data set associated with it, or when the number of dump VTOC copies kept is zero, DFSMShsm cannot provide the following:

Physical data set restore support from the associated dump copies
Listing capabilities for the dump copy using the DUMPCONTENTS parameter with the LIST DUMPVOLUME command
VTOCCOPIES are not needed for data set recovery from copy pools, so specifying VTOCCOPIES(0) for dump classes used for copy pool dump is recommended.

Dump VTOC copy data sets are not created for or maintained for dumps of DFSMShsm-owned volumes.

Defaults: If you do not specify VTOCCOPIES when a dump class is defined for the first time, a default of 2 is used for non-copy pool volumes, and a default of 0 is used for copy pool volumes.

If a dump class is already defined and certain characteristics are changed, and if VTOCCOPIES is not specified, the previous specification remains unchanged.