Firewalld on Centos 7 with dynamic IP

I wanted to allow my home IP to much more ports then standard.

Therefore, I searched for a solution to allow a DNS name to the Firewalld.

That is not possible? It is, with a smal script I wrote and I want to share.

First, you need a dyndns provider for your home IP like http://freedns.afraid.org/

Then you create a file with my script and edit the hostname.

Also, make it executable.

Copy/paste this:

^#/bin/sh
^date
^{#check if file already there if not, create it}
^{if [ -r /run/myip ]}
^then
^{echo "file there"}
^else
^{echo "file not there"}
^{dig +short i.home.mollberg.de > /run/myip}
^{firewall-cmd --zone=public --add-rich-rule='rule family="ipv4" source address="'$myipnew'" accept'}
^fi

^{#get old IP}
^{myipold=$(</run/myip)}
^{echo "$myipold"}
^{#get new IP}
^{myipnew=$(dig +short YOUR-DNS-NAME-HERE)}
^{echo "$myipnew"}

^{#compare new and old ip, do nothing if nothing changes, remove old ip and allow new IP if IP has changed}

^{if [ "$myipold" = "$myipnew" ]}
^then
^{echo "same IP"}
^else
^{echo "diff IP"}
^{firewall-cmd --zone=public --remove-rich-rule='rule family="ipv4" source address="'$myipold'" accept'}
^{firewall-cmd --zone=public --add-rich-rule='rule family="ipv4" source address="'$myipnew'" accept'}
^{dig +short YOUR-DNS-NAME-HERE > /run/myip}
^fi

Now add a cron job like this running every hour:

^{0 * * * 0 root /home/user/MyIP.sh >> /var/log/myip.log}

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Firewalld on Centos 7 with dynamic IP