Dear all,

I have the following situation.

I have an firewall in fornt of zimbra apliance.
I forward all request to port 25 to the zimbra apliance but zimbra doesen't respond.

Here the firewall rule.

-A PREROUTING -d RealIP -p tcp -m tcp --dport 25 -j DNAT --to-destination 192.168.0.111
-A POSTROUTING -s 192.168.0.111 -p tcp -m tcp --dport 25 -j SNAT --to-source RealIP

Where 192.168.0.111 is the ip of zimbra apliance.

If I send an telnet comand to ip 192.168.0.111 por 25 from local network (192.168.0.x) the zimbra apliance it's alive:

telnet 192.168.0.111 25
Trying 192.168.0.111...
Connected to 192.168.0.111.
Escape character is '^]'.
220 xyz.com ESMTP Postfix

I'm sure that the firewall it's ok because I use iperf to emulate port 25 to another host and it's work the firewall rule.

Can anyobdy explain me what I nett to change in main.cf postfix configuration file to work.

Thaks for support