How to disable IPv6 for postfix service node?


How to disable IPv6 on a Postfix Service Node?


Enforcing Postfix to use IPv4 an be done by specifying inet_protocols parameter in configuration file:

  1. Open /etc/postfix/ with text editor (for example, vi) on the Postfix service node.
  2. Change inet_protocols value from inet_protocols = all to inet_protocols = ipv4.
  3. Restart Postfix service:
    # /etc/init.d/postfix restart

It defines what protocols Postfix will use, when it makes or accepts network connections, and also controls what DNS lookups Postfix will use, when it makes network connections.