Firewall and Proxy Server HOWTO

• Index
• Introduction
• Understanding Firewalls
• Firewall Architecture
• Setting up the Linux Filtering Firewall
• Software requirements
• Preparing the Linux system
• IP filtering setup (IPFWADM)
• IP filtering setup (IPCHAINS)
• Installing a Transparent SQUID proxy
• Installing the TIS Proxy server
• The SOCKS Proxy Server
• Advanced Configurations
• Making Management Easy
• Defeating a Proxy Firewall
• APPENDEX A - Example Scripts
• APPENDEX B - An VPN RC Script for RedHat

4. Setting up the Linux Filtering Firewall

4.1 Hardware requirements

Filtering firewalls don't require fancy hardware. They are little more then simple routers.

All you need is:

1. a 486-DX66 with 32 meg of memory
2. a 250m hard disk (500 recommended)
3. network connections (LAN Cards, Serial Ports, Wireless?)
4. monitor and keyboard

With some systems by using a serial port console, you can even eliminate the monitor and keyboard.

If you need a proxy server that will handle lots of traffic, you should get the largest system you can afford. This is because for every user that connects to the system it will be creating another process. If you will have 50 or more concurrent users I'm guessing you will need:

1. a Pentium II with 64meg of memory
2. a two gig hard disk to store all the logs
3. two network connections
4. monitor and keyboard