We have two domains with AD two-way trust and Exchange GAL synchronization done via Forefront identity Manager 2010. We have a problem with meeting room reservation, user from domain A is trying to book meeting room from domain B (there is a contact object in domain A for this meeting room from domain B). The problem is that such room is not sending response confirmation email to user and meeting room is visible as tentative. I alreadyset "externally secured" option on receive connectors in domain B:
exchange 2010 server - receive connector role:HubTransport, scoping exchange server in domainA IP port 25, security: tls and externally secured
3x exchange 2013 servers - receive connector role:FrontendTransport, scoping exchange server in domainA IP port 25, security: tls and externally secured
I am not sure whether this is enough configuration for receive connectors, what about receive connector for hubtransportrole on 2013 exchange servers? Should I also configure them, what ports?
Domain A: one exchange 2013 server
Domain B: one exchange 2010 server (meeting rooms hosted in db on this server) and 3 exchange 2013 servers in DAG, prepared to migrate mailbox db from 2010 server