Firewall configuration in CentOS 7

CentOS 7 introduced firewalld to replace iptables. As a result, the "system-config-firewall-tui" command no longer works (unless you re-install iptables).

The equivalent way of adding in a couple of ports to the firewall rules is as follows:

sudo firewall-cmd --add-port=4505/tcp
sudo firewall-cmd --add-port=4506/tcp

The above will add rules to open the ports, but the change won't survive a reboot. To make the changes permanent, just add the "--permanent" flag to the command.