F-SECURE INTERNET GATEKEEPER FOR LINUX 4.01 Administrator's Manual page 124

iptables setting for the Gateway server
Follow these instructions to redirect the access to ports 25 and 110 of eth1 (192.168.2.1) to 9025 and
9110.
• iptables – commands:
# iptables -t nat -A PREROUTING -d 192.168.2.1 -p tcp --dport 25 -j REDIRECT
\
--to-port 9025
# iptables -t nat -A PREROUTING -d 192.168.2.1 -p tcp --dport 110 -j REDIRECT
\
--to-port 9110
# /etc/rc.d/init.d/iptables save
Settings for F-Secure Internet Gatekeeper for Linux
Set the port numbers of the parent server to 9025 and 9110, and the parent server to be the mail
server (localhost:25, localhost:110)) at the web console.
Proxy settings
SMTP proxy: On
Proxy port: 9025
Global settings
Parent server
Host name: localhost
Port number: 25
POP proxy: On
Proxy port: 9110
Parent server:
Host name: localhost
Port number: 110
Client settings
Set the mail server to 192.168.2.1.
Make sure that the client can send and receive mails.
F-Secure Internet Gatekeeper for Linux/Administrator's Guide
124