Specifying when the data on dump volumes becomes invalid

The data on dump volumes is of value until the data on the original volume has changed significantly. In the meantime, you are making new dump copies periodically. After some period, you want to indicate to DFSMShsm that the old dump copies are no longer of value. You can do this with the RETENTIONPERIOD subparameter of the DUMPCLASS parameter.

Use the RETENTIONPERIOD subparameter to specify a number of days for which DFSMShsm considers data on the dump volumes as valid. After the period specified by RETENTIONPERIOD has elapsed, the volumes become eligible to be reused, either automatically or manually.

Because you are making dump copies weekly for use at your site, consider all data on volumes dumped to dump class ONEWEEK to be invalid after three weeks. Similarly, consider data on volumes dumped to dump classes TWOWEEK and FOURWEEK to be invalid after three cycles. If you want to retain the dump copies until the full 100 generations have been made, you can specify NOLIMIT as the value for the retention period. Change the DEFINE DUMPCLASS commands as follows:

DEFINE DUMPCLASS(ONEWEEK AUTOREUSE -
DATASETRESTORE FREQUENCY(7) NORESET -
RETENTIONPERIOD(21))
DEFINE DUMPCLASS(TWOWEEK NOAUTOREUSE -
NODATASETRESTORE FREQUENCY(14) -
DISPOSITION('SEND OFFSITE BIWEEKLY') -
NORESET RETENTIONPERIOD(42))
DEFINE DUMPCLASS(FOURWEEK NOAUTOREUSE -
NODATASETRESTORE DAY(28) -
DISPOSITION('SEND OFFSITE MONTHLY') -
NORESET RETENTIONPERIOD(84))