@FaP Clone this repository to somewhere on your server (I always recommend /root/git😞 https://github.com/FOGProject/fog-community-scripts
There’s a tool in there called updateIP. First, you adjust your IP address for your OS as needed, then you would run this script which would update all the IPs in FOG and also update DHCP configuration if you have that enabled on your fog server too.
Do let me know how it goes.