In z/VSE 5.1 we implemented a small customer requirements. It is available since June last year. We introduced the IJBVMID system parameter. It contains the 8 byte z/VM user-id, when z/VSE is running under z/VM. It contains 8 blank characters, when z/VSE is running in a LPAR. E.g. you may use conditional JCL and check the IJBVMID value and execute different JCL for your test userid than your production userid.