Iptables provides packet filtering, network address translation (NAT) and other packet mangling.

Two of the most common uses of iptables is to provide firewall support and NAT.

List all the rules in effect (by default, none):

 # iptables --list

 Chain INPUT (policy ACCEPT)
 target     prot opt source               destination


Configuring iptables manually is challenging for the uninitiated. Fortunately, there are many configuration tools (wizards) available to assist: e.g., fwbuilder, bastille, ferm.

Manual configuration:

Configure iptables so that it starts with your system

 # update-rc.d iptables defaults

Save the firewall rules to be used when your firewall is inactive (e.g. a set of empty rules)

 # /etc/init.d/iptables save_inactive

Add your rules (to be done)

 # 

After you're done, save the rules you created using

 # /etc/init.d/iptables save_active

More to come... this is just a start since I noticed there wasn't much info on iptables.


Resources: