Setting Up a Linux Gateway
Setting up the Linux client (nazareth, 192.168.0.2) is very easy. All you need do is issue the following command on nazareth:
route add default gw antioch
Now try pinging an external site (let's say www.ssc.com) to see if it responds:
ping www.ssc.comIf it responds, you are in business! If it doesn't, check the FAQ included with the mini-HOWTO for solutions to frequently encountered problems.
Setting up the Windows client is a bit more troublesome. Here are the steps involved:
Go to the Control Panel and double-click Network.
Locate the icon that represents your TCP/IP protocol for your network interface card. Open up its Properties.
Click on the Gateway tab. Add 192.168.0.1 as the gateway.
Click on the DNS Configuration tab. Under DNS Server search order, add your ISP's DNS server IP addresses.
Press OK on all the dialog boxes.
Reboot the machine.
Again, test your gateway by accessing an external site (use ping or your web browser or whatever). If all goes well, you should be able to do most things you usually do on the Internet.
There are a few things you should be aware of when setting up your Linux gateway.
First of all, certain Internet applications may not work well with our setup. For a list of what works and what does not, see the latest version of the IP Masquerade mini HOWTO.
A few applications may require you to load specific kernel modules. In our case, for example, we have already loaded ip_masq_raudio, which will take care of any Real Audio connections. If you want to run Quake, VDOLive or CUSeeMe, you will need to load their respective kernel modules.
Another thing to keep in mind is that applications on your Linux client machine may not work properly if your gateway is not connected to the Internet. One such application may be sendmail. Therefore, if you know your gateway is off-line, you may want to remove your gateway's IP address from your Linux client's routing table. To do so, just issue the following command on the Linux client machine:
route del default
A Linux gateway offers a great solution to using and sharing a connection to an external network. Linux is extremely suitable for use as a gateway for both home and commercial networks because it is low in cost and reliable.
Lawrence Teo (email@example.com) recently completed his Bachelor of Computing degree from Monash University, Australia. He has been using Linux since 1997 and has been glued to it since. His other interests include security, cryptography, webmastering and software development. Lawrence aspires to be a UNIX system administrator one day.