I applied some MS updates last night and now mail is stuck between my DC's. I have 3 sites - TPA, ORL, and ATL. Each site has connectors TPA -> ORL, ATL > TPA - etc...
In System Manager I see a queue building up for "ORL-to-TPA (Routing Group Connector)" with a status of "The remote server did not respond to a connection attempt."
I can't find anything in Event Viewer. Dcdiag is running ok. The connectors appear to be setup correctly. I can ping all the DC's by name from eachother.