On our HT servers we have a receive connector, that is basically an open relay, which has a specific allow list on it for other servers on our network. This connector though keeps saying that it has a 4.3.2 error. However, reporting from some servers says no error, and on others it does. For example, running "get-transportserver | test-smtpconnectivity" yeilds a success for all connectors when run from the mailbox servers, but run test-smtpconnectivity from the local HTs and it says error for this recieve connector. telnetting to the ip on port 25 fails with 4.3.2 as well EXCEPT from the Mailbox servers.
Info from powershell:
RunspaceId : 30374db7-67a8-4772-8d00-b8ff97a14151
Server : server
ReceiveConnector : Anonymous Relay (server)
Binding : 192.168.100.218:25
EndPoint : 192.168.100.218:25
StatusCode : Error
Details : 421 4.3.2 Service not available
Identity : server\Anonymous Relay (server)\192.168.100.218:25\192.168.100.218:25
IsValid : True