Setting up a Firewall for Ubuntu

Ubuntu 8.04 has ufw, a built-in tool that is way easier to use than iptables. Setup the default rule to deny everything we don't specifically accept

ufw default deny

Allow anything from local network

ufw allow 192.168.0.0/24

Allow access to specific ports, in this case ssh and http

ufw allow 22/tcp
ufw allow 80/tcp

Enable the firewall

ufw enable

Review the rules that were setup

ufw status