Using moblock according to
http://moblock-deb.sourceforge.net/
additional how to under: https://help.ubuntu.com/community/MoBlock
Very important: make sure you can still talk to your headless machine!! add doing
sudo nano /etc/blockcontrol/blockcontrol.conf
ssh allow all incoming traffic on port 22
WHITE_TCP_IN="22"
otherwise you will be blocked out!
