Firewall configuration for Ubuntu server

Hey
Anyone can explain a best and easy method to configure a firewall in Ubuntu server. I'm new to configure it. Please tell me an easy method.
Thanks advance.

 

I guess you have a basic knowledge in Networking & Linux. Refer these guides.

http://iptables-tutorial.frozentux.net/iptables-tutorial.html

Code (markup):

http://www.iptables.org/

Code (markup):

 

Thanks eng152, But i need something as a tutorial.

 

There are many goo dtutorial at netfilter.org, see the url below

http://netfilter.org/documentation/index.html#documentation-howto