<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><li>If you are disconnected from a VM: Some of the traffic between your host and VirtManager goes through IPtables.<br> 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.</li></ol>

 <ol><li value="34">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>