:*When you install Iptables in CentOS it already has some rules predefined.

:*You will always get the default rules if you restart the iptables service.

<ol><li value="2">Save your rule in a bash script (.sh file) so you don't lose it and can rerun it easily.</li></ol>

{{Admon/important |Disconnected from VMs|Some of the traffic between your host and VirtManager goes through IPtables. When you mess with IPtables rules on the host - you may end up losing the console connection to the virtual machines. Don't worry, they're still running and you can still use them.}}

<ol><li value="3">If your command didn't work - the easiest thing to do is:<ul><li>Reload the default rules. You can do that by restarting the iptables service (you can also do that at the beginning of your shell script).</li><li>Then run your script with all the working iptables commands that you already finished.</li><li>Go back to writing the rule that didn't work.</li></ul></li></ol>