Examples: Saving and Restoring Iptables Rules

http://www.cyberciti.biz/faq/how-do-i-save-iptables-rules-or-settings/

In this example, save current iptables firewall rules to a file called /root/dsl.fw, enter:
# iptables-save > /root/dsl.fw
To restore iptables rules, enter:
# iptables-restore < /root/dsl.fw

To restore rules automatically upon Linux system reboot add following command to your /etc/rc.local file, enter:
# vi /etc/rc.local
Append the line:
/sbin/iptables-restore < /root/dsl.fw
Save and close the file. Please note that under Red Hat enterprise Linux (RHEL) / CentOS / Fedora Linux you can use following commands to save and restore firewall rules. To Save the rules to /etc/sysconfig/iptables file:
# /etc/init.d/iptables save
To restore the rules from /etc/sysconfig/iptables file:
# /etc/init.d/iptables start
If you are using Debian / Ubuntu Linux open /etc/network/interfaces:
# vi /etc/network/interfaces
Append the line to eth0 section:
post-up iptables-restore Close and save the file. Reboot the system.