Target server is not communicating(polling) with master SQL Server
Does the target server know that it is a target server? In SSMS, does Agent say that this is a TSX?
I have a feeling that the fact that you are in an MSX environment is stored in the registry instead of a system database.
I just looked on an TSX server, an SQL Server instance named &quot;B&quot;. The master server is an instance named &quot;A&quot; (on the same machine, this is a test setup). I have a key named:
Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\MSSQL15.B\SQLServerAgent
In above key, I have an entry named MSXServerName with the name of the master server.
Above is what I would fix first.
After fixing that, I would check the SQLAgent.out file on both MSX and TSX. And possibly resync the TSX server using sp_resync_targetserver. I blogged about this here:
http://sqlblog.karaszi.com/resynchronizing-a-target-server-msx-tsx/