Sending emails using a different IP address

You can send emails of your server from an additional IP of your server instead of the main IP using iptables. Here is the iptable command:

iptables -t nat -A POSTROUTING -o eth0 -p tcp -j SNAT -dport 25 –to-source IPAddress

where, IPAddress is the additional IP of your server. To save the rule, execute

service iptables save

This will make the settings permanent and you can check the rule using

iptables -L -t nat