It is not "necessary" to use BRMS. Back when I used a virtual tape image catalog I did though. Then I could ftp that image catalog to another system where there was a physical tape and do a DUPMEDBRM. This kept track of objects which was easily retrievable by WRKOBJBRM.
The reason you are getting that message is because BRMS requires that you install 5770SS1-18-Media and Storage Extensions. This adds hooks into all the save commands. Kind of like exit point programs. If it didn't, then how would BRMS know that you used one of the tapes listed in WRKMEDBRM for a save outside of BRMS?
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Robert Berendt IBMChampion
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