Suppress Logon Messasges

CMPRINT contains Security and Logon messages. I would like to change the SYSOUT to a file and print only my output data, not the messages.
Are those messages suppressed in production? I cannot find any difference in my test JCL vs. the production JCL but those messages don’t show in production.
Please explain.
Thank you

You cannot suppress these messages, but you can re-route your output to another printer (i.e. DDNAME), effectively separating the content. This is done with the MAINPR parameter, which can be specified as an override in your JCL.

For example, MAINPR=4 will send your print lines to CMPRT04 instead of CMPRINT.

OK, I will do that. Thank you!!!