Install Firewall

Introduction:

This covers intallation of 'iptables'; Linux's built-in firewall. iptables is a little more than a firewall, it also routes packets from the internet to the local network.

Aim:

Protect the network from intrusion.

Requirements:

None.

Procedure:

• Log in as root
• Open Terminal
• # cd
• # mkdir firewall
• # cd firewall
• Copy the following script into this directory - I usually put it on a floppy. (Hint: right-click the link and choose 'Save link as...'):
• iptables.sh
  
• Run the installer:
• # ./iptables.sh
  
• Make rules permanent:
• # service iptables save
• # service iptables start
• This is the result:
  

# service iptables save Saving firewall rules to /etc/sysconfig/iptables: [ OK ] # service iptables start Flushing firewall rules: [ OK ] Setting chains to policy ACCEPT: mangle nat filter [ OK ] Unloading iptables modules: [ OK ] Applying iptables firewall rules: [ OK ] #

Testing:

This will be extensively tested when the network is connected up.