Quick Setup APF firewall

in your server command prompt
** You need to have iptables installed in your server **

wget http://www.r-fx.ca/downloads/apf-current.tar.gz
tar zxf apf-current.tar.gz
cd apf-x
./install.sh
edit /etc/apf/conf.apf

IFACE_IN="xxx"
IFACE_OUT="xxx" -- replace xxx with internet exposed interface

IFACE_TRUSTED="yyy" -- -- replace xxx with internal network where firewall not applicable ( if available ) .

change
# Common inbound (ingress) TCP ports
IG_TCP_CPORTS="22,80,4443" --- mention the ports that you want to keep open in external interface .

A lot of other directives are there to manipulate your config .

Only basic configs are mentioned here .

then start apf " apf -s" andf test your firewall

If all set just set DEVEL_MODE="0" in conf.apf then
stop apf " apf -f"
and start "apf -s"