How to save IPTABLES rules

The following lines allow SMTP and HTTP traffic through an IPTABLES firewall. But this information is not automatically saved and reloaded if the service restarts.

iptables -I INPUT -p tcp –dport 25 -m state –state NEW,ESTABLISHED -j ACCEPT
iptables -I INPUT -p tcp –dport 80 -m state –state NEW,ESTABLISHED -j ACCEPT

Whenever you make a change to your firewall, on a Fedora/CentOS type system, you will want to save the changes.

The output can be redirected to a file.

# iptables-save > /root/firewall-rules
The following command line restores all rules from /root/firewall-rules assuming that the file /root/firewall-rules exists.

# iptables-restore < /root/firewall-rules

By default, iptables-restore deletes all existing rules before restoring the saved rules. If the saved rules are to be appended to existing rules, use the -n or –noflush option.

Save Your Firewall and Load on Restart

You will need to edit the /etc/sysconfig/iptables-config as root to help iptables save and reload your firewall correctly. Be sure the following settings are changed to “yes”.

# Unload modules on restart and stop
# Value: yes|no, default: yes
# This option has to be ‘yes’ to get to a sane state for a firewall
# restart or stop. Only set to ‘no’ if there are problems unloading netfilter
# modules.

# Save current firewall rules on stop.
# Value: yes|no, default: no
# Saves all firewall rules to /etc/sysconfig/iptables if firewall gets stopped
# (e.g. on system shutdown).

# Save current firewall rules on restart.
# Value: yes|no, default: no
# Saves all firewall rules to /etc/sysconfig/iptables if firewall gets
# restarted.