The CONNX for VSAM / QSAM / PDS Started Task product supports two methods for setting environment variables. The first and easier of the two methods, discussed in section 3.4.1, is to enter the environment variables as standard variable / value pairs (=variable =value) in separate records in a partitioned data set member. Refer to the discussion of the pre-set environment variables in member CNXPARMS of CONNX.VVRR.STASK.CNTL. Environment variables set using this approach are passed in the parameter string of the EXEC PGM=CNXRUNB statement in the CNXVSAM / CNXVSCT JCL procedures. For example,  starting two instances of the CNXRUNB Listener requires two separate CNXPARM members so that two unique TCP/IP ports can be defined via the =CNXRUNPORT environment variable. Similarly, the CONNX tracing logic can be enabled in one CNXPARMS member and disabled in another via the =DEBUG environment variable.

The second method of managing CONNX environment variables is via the CNXCFG REXX command file, which invokes program CNXCFGB to update the CNXCFG VSAM KSDS. Using this method, you can insert, update and delete persistent CONNX environment variables which reside in a key-sequenced VSAM file (CONNX.VVRR.STASK.CNXCFG). The CONNX environment variables defined via this method can be shared across multiple instances of the CNXVSAM/CNXVSCT started task(s) or batch job(s).