After having applied some maintenance on three NetMaster regions running on the same sysplex, when these regions are recycled almost at the same time, one starts without errors but the remaining two get several MS0006 Message definition aaaaaaaa does not exist errors, where aaaaaaaa can be any of the NetMaster error messages. For example:
MS0006 Message definition IPDI5273 does not exist
USS uid=1018891070(SOLVE) gid=3111(STARTASK)
MS0006 Message definition IPDI5274 does not exist
MS0006 Message definition IPDI5275 does not exist
MS0006 Message definition RMAOM001 does not exist
Release : 12.2
Component: NetMaster suite
The regions are sharing the same MODSDIS VSAM dataset and all the three ones have VSAMUPDATE (automatic VSAM updates) feature turned on.
As it can be read on the Update VSAM Data Sets section of the documentation, if MODSDIS file (and panel dataset also) is shared among some regions, VSAMUPDATE can be enabled only on one of the regions:
To prevent file corruption in cases where the MODS and Panels datasets are shared between NetMaster Regions, verify that VSAMUPDATE is enabled on only one region.
In this scenario (MODSDIS shared, maintenance applied, the regions restarted at the same time), a best practice is to start the only region with VSAMUPDATE turned on first, then the other ones.