Overview

This topic describes how administrators should work with iptables. openshift-sdn takes care of adding the necessary iptables rules to make it work. Kubernetes and Docker also manage iptables for port forwarding and services.

Restarting

Docker doesn’t monitor the iptables rules that it adds for exposing ports from containers and hence if iptables service is restarted, then these rules are lost. So, to safely restart iptables, it is recommended that the rules are saved and restored.

$ iptables-save > /path/to/iptables.bkp
$ systemctl restart iptables
$ iptables-restore < /path/to/iptables.bkp