Ubuntu Firewall

Ubuntu includes ufw (uncomplicated firewall) by default, but it is not enabled.

Configure the Uncomplicated FireWall via CLI
sudo su ufw allow ssh ufw allow 80/tcp ufw allow 443/tcp ufw allow 1719/udp ufw allow 1720/tcp ufw allow 3478/udp ufw allow 3479/udp ufw allow 5002/tcp ufw allow 5003/udp ufw allow 5060 ufw allow 5061 ufw allow 5070 ufw allow 5080 ufw allow 5081 ufw allow proto udp from any to any port 16383:32768
 * 1) for Fusion
 * 1) for FreeSWITCH

ufw default deny ufw enable ufw logging on ufw status Happy Firewalling!

More Information
https://help.ubuntu.com/10.04/serverguide/C/firewall.html

https://help.ubuntu.com/community/UFW man ufw