I have a new install of Zimbra (the OS edition) in a virtual machine for testing, and I'm having trouble with incoming and internal mail. Everything gets deferred with the status message of "connect to sub.domain.tld[public-ip-address]: connection refused".
Outgoing mail seems to work fine but even mail sent from one Zimbra user to another gets deferred with that error status.
The VM Zimbra is running on has the one interface with the address 192.168.220.2, gets external connections from one of the host machine's public addresses via iptables NAT rules, and sees the outside world via NAT (masquerade) also.
The ip address listed is the public IP, not the one the Zimba MTA is listening on, which I though may be the problem, but I can telnet from the Zimbra VM to that address on port 25 and I get the welcome message from postfix as expected (port 25, amongst others, is being forwarded to the VM's local address via iptables (NAT) rules).
Should it not be trying to connect to the local address (192.168.220.2), as that is what the server name is associated with in /etc/hosts? Though as I can connect via telnet to the external address on port 25, is there some other problem? Is it trying to transfer mail on a different port that I need to arrange a forward for? Should it be trying to connect to anything for internal mail transfers? I woudl have thought mail form email@example.com to firstname.lastname@example.org would be shuffled around the mail store without the need for a TCP connection.
Any pointers you can give for finding out what is wrong with my setup would be greatly appreciated.