Summary: The ACF2/CICS ACFM transaction can be used for temporary changes to the CICS initialization parameters, for permanent changes the CICS region needs to be re-cycled.
The CA ACF2 CICS interface is totally parameter driven by system parameters that can be defined in the following two ways.
1) CA ACF2 options for each CICS region are specified through a series of system parameters, which are read from a data set corresponding to the ACF2PARM DD statement in the CICS JCL.
2) The CICS interface initialization options might also be defined by a new set of CA ACF2 Infostorage database records which you maintain using standard ACF2 facilities like the ACF command, the ISPF panels, and the CA Web Administrator for ACF2.
The initialization parameters are read during system initialization to determine the initial size of the data area used by system options and to set up the actual environment specified by the parameters.
The CA ACF2 master terminal transaction (ACFM) can modify many of the parameters in the currently executing CICS. ACFM does not, however, update the parameter data set. Unless the parameter is changed in the parameter data set, the original system options are in effect when CICS is restarted.
For permanent changes to the initialization parameters to take effect, the changes must be made prior to the CICS region starting up or if the region is already up, the site can make temporary changes with the ACFM transaction or the region would need to be re-cycled.
Details can be found in the Chapter 5: CICS Interface Parameters in the CA ACF2™ for z/OS CICS Support Guide.