How To change Name-Server Ip on a cPanel Server
The file that actually handles WHM > DNS Functions > Nameserver IPs area is at
/var/cpanel/nameserverips.yaml .
So if you want to change the name-server Ip on your cPanel Server, you’d want to make a backup of that file first and then modify it:
cd /var/cpanel cp nameserverips.yaml nameserverips.yaml.back nano nameserverips.yaml
and modify the IPs there