If you use a firewall, you must disable it before you run the cPanel & WHM installation.
Red Hat® Enterprise Linux® and CentOS distributions allow you to disable the firewall for the operating system’s installation configuration. We strongly recommend that you use this method.
Run the following commands to deactivate the firewall:
/etc/init.d/iptables save /etc/init.d/iptables stop /sbin/chkconfig --del iptables
Run the following commands to deactivate the firewall, where
~/firewall.rules represents the firewall rules file:
iptables-save > ~/firewall.rules systemctl stop firewalld.service systemctl disable firewalld.service
For cPanel & WHM to run on your web server, the OS firewall must remain disabled. When the installation process finishes, configure your firewall with a third-party client. We recommend that you use APF or CSF.