index   Previous   Next

To configure the iptables to install a linux firewall like firestarter or in debian iptables-persistent or other firewall like shorewall.
If your other network computer share the Internet connection the enable the ip_forward from the
/etc/sysctl.conf and then run the sysctl -p for the changes to take effect:

# Uncomment the next line to enable packet forwarding for IPv4

net.ipv4.ip_forward=1

Now run the command:

sysctl -p

To list your current iptables rules run the command:

iptables -l

To print your current iptables rules run the command:

iptables-save Or save to a file:

iptables-save > iptables-config

To delete all the iptables rules run the command:

iptables --flush

These are the already configured rules for a network running the web and mail server,with forwarding and masquerading
enabled,
run the restore command to restore from the file rules :

iptables-restore < rules

To restore the iptables rules at boot put a script firewall in the /etc/init.d with these lines:

#! /bin/sh
### BEGIN INIT INFO
# Provides: custom firewall
# Required-Start: $remote_fs $syslog $network
# Required-Stop: $remote_fs $syslog $network
# Default-Start: 2 3 4 5
# Default-Stop: 0 1 6
# Short-Description: firewall initscript
# Description: Custom Firewall
### END INIT INFO
/sbin/iptables-restore < /etc/iptables/rules

and then run the:

update-rc.d -f firewall defaults

This will restore the iptables rules in each boot, remember to put the rules in the /etc/iptables dir.
These are all-in-one-rules iptables commands to run one by one.

---