Postfix - suddenly stopped working?

[louis-m]

Been running postix forwarder for the last month or two without issue and all of a sudden, it stops working. No update has occured which makes it even stranger.
Despite my valiant attempts, I still can't get it to go.
In my desperation, I have now reinstalled it wiping the config etc but still it refuses to budge.
I now have the following in my logs:

Jan 6 19:16:45 postfix/postfix-script[92419]: fatal: mail system startup failed
Jan 6 19:16:44 postfix/master[91853]: fatal: daemon initialization failure
Jan 6 19:16:43 postfix/master[92197]: fatal: /usr/pbi/postfix-amd64/etc/postfix/master.cf: line 3: no valid IP address found: smtp
Jan 6 19:16:40 php: /status_services.php: The command '/usr/local/etc/rc.d/postfix.sh stop' returned exit code '1', the output was '/usr/pbi/postfix-amd64/sbin/postconf: warning: /usr/pbi/postfix-amd64/etc/postfix/master.cf: unused parameter: user=postfix'
Jan 6 19:16:40 postfix/postfix-script[60417]: fatal: the Postfix mail system is not running
Jan 6 19:16:26 postfix/postfix-script[52672]: fatal: mail system startup failed
Jan 6 19:16:25 postfix/master[52233]: fatal: daemon initialization failure
Jan 6 19:16:24 postfix/master[52337]: fatal: /usr/pbi/postfix-amd64/etc/postfix/master.cf: line 3: no valid IP address found: smtp
Jan 6 19:16:24 php: /pkg_edit.php: Postfix setup completed

Any idea?

[biggsy]

Just guessing but could your public IP or the IP of your back-end mail server have changed?

Check your basic configuration process against this:

http://forum.pfsense.org/index.php/topic,70541.msg384977.html#msg384977

[louis-m]

Backend mail server hasn't been changed at all. It's exchange 2013 with a smart host configured at the pfsense address.
If I set pFsense to listen on loopback, exchange will not connect to the pfsense smart host whereas if I leave it at listen on LAN1, LAN2 etc, exchange can connect.
But it still doesn't foward even if it connects.
If I send from gamil to pfsense, I can see mail hitting the firewall on port 25 but it disapppears then. No NDR from gmail etc so it looks a though it's gone through but nothing in the postifx queue either? Where is the mail going? Weird!

[X505]

I got the same issue and selecting interface(s) in the "Listen on" list instead of "listen on all interfaces/ip addresses" solves it.