Bind Postfix Mail Server To Localhost or Specific IP Address Only

Q. How do I bind Postfix MTA to specific IP address such as 127.0.0.1 or 202.5.1.2?

A. Postfix allows you to listen on a particular IP address. By default MTA will list on all network interfaces and loopback. You need to setup inet_interfaces parameter. You need Postfix version 2.2 and later to use this feature. The parameter also controls delivery of mail to [email protected][ip.address].

Postfix IP address bind configuration

Open /etc/postfix/main.cf file:
# vi /etc/postfix/main.cf
Append / modify line as follows to bind to localhost (127.0.0.1) only:
inet_interfaces = 127.0.0.1
If you need to bind to 127.0.0.1 and 202.5.1.2, enter:
inet_interfaces = 202.5.1.2,127.0.0.1
Save and close the file. You need to stop and start Postfix when this parameter changes. So type the following to restart Postfix:
# /etc/init.d/postfix restart
Verify that everything is working fine:
# netstat -tulpn | grep 25
# tail -f /var/log/maillog

Posted by: SXI ADMIN

The author is the creator of SXI LLC and a seasoned sysadmin, DevOps engineer, and a trainer for the Linux operating system/Unix shell scripting. Get the latest tutorials on SysAdmin, Linux/Unix and open source topics via RSS/XML feed or weekly email newsletter.