After trying to run TPX on a second LPAR, even though the second started task was stopped, the APTPX VTAM task was active on both LPARS.
When I varied the non-production APTPX task inactive, the non-production LPAR instantly became available.
I need to understand why this happens and how to prevent it.
TPX / VTAM
This WILL cause unpredictable results, since there would be multiple LUs with same name in the network. You can only have one node activate on one host at a time unless the LU names (APPLs in this case) have symbolic that would make them unique on each host.