Specifying how many versions to keep for each backed up data set

For non-SMS-managed storage, the number of backup versions to retain is a DFSMShsm host-wide specification.
Note: You can use the (H)ALTERDS command to specify a different value from the DFSMShsm host-wide default for individual data sets.
As with SMS-managed storage, depending on the record length that is used to define the BCDS, DFSMShsm can maintain up to 29, or up to 100, backup versions of any data set. Within that upper limit, the VERSIONS parameter of the SETSYS command controls the number of backup versions to be retained. For the example system, the following command is added to the ARCCMDxx member for each DFSMShsm host:
SETSYS VERSIONS(5)

If you use the RETAINDAYS keyword when you create a data set backup copies, and active backup copies with an unmet RETAINDAYS values are rolled off, DFSMShsm maintains them as retained backup copies. DFSMShsm can maintain more than enough retained copies for each data set to meet all expected requirements.

Related reading