We will be upgrading from z/OS 2.4 to zOS 2.5.
The IBM Planning doc for upgrading to z/OS 2.5 states that because the VTAM topology agent and the VTAM Common Management Information Protocol (CMIP) services on z/OS will no longer be supported after z/OS V2R4, an alternate method of obtaining SNA topology data must be used. IBM recommends using the SNA network monitoring network management interface (NMI) to monitor SNA Enterprise Extender and High Performance Routing data.
Netmaster for TCP/IP Release : 12.2
NetMaster never used the OSIMGMT option and thus there's no need for that parm.
NetMaster SNA Automation has always done its discovery via a multitude of VTAM display commands.
Netmaster already uses the IBM NMI interface for EE/HPR data, so that is also not a concern.
The IBM NMI was available in 12.1 with PTFs, and in 12.2 as the default.
To verify whether the IBM NMI is active, check the SOLVESSI STC output for this message.
NFST05 TRACE NMI IN USE, BUFSZ=(128M,16M,32M,48M)
If it is not yet in use, please refer to this section of our Installing and Upgrading Guide for security and configuration requirements.