In PARMLIB member IGDSMSxx, you specify the setting for the system as follows:

CA_RECLAIM (NONE | {DATACLAS | DATACLASS})

where

NONE

Disables CA reclaim for the system, regardless of the value for the CA reclaim attribute in data class or catalog entries. This is the default. Not specifying CA_RECLAIM has the same effect as specifying CA_RECLAIM(NONE).

DATACLAS or DATACLASS

Enables CA reclaim for the system. CA reclaim is in effect for all eligible data sets for which CA reclaim is not disabled with the data class attribute or the ALTER command. You can use the CA Reclaim attribute in each data class to enable or disable CA reclaim for new data sets as they are defined.