Building a floppy-based router
Building a floppy-based router, By netfreak
The "broadband revolution" has come and many home/small office Internet users subscribe to such ISPs as @home, RoadRunner, Qwest, and Telus. The problem with most of these services is the limit on IP addresses given to each customer. Instead of forking out an addition to your monthly bill for more IPs, why not build a simple router?
You'll need at least a 386 computer with an FPU and 12 megs of RAM. You'll also need two Ethernet cards. For compatibility issues, use 3com, Intel, or NE2k cards. If you use ISA cards, be sure to record the IO and IRQ addresses. If you don't know them, visit the manufacturer's homepage (most offer MS-DOS tools for finding the IO/IRQ). For convenience, use the smallest PC case you can find. Your constructed PC should have the following: 386+ w/ FPU, 12+ MB RAM, 1.44mb floppy drive, 2 NICs, keyboard, any video card and monitor. I also recommend a slot-fan to keep air circulation in the PC. To connect your internal machines to the router, attach a hub or switch to the router's internal NIC.
You'll need a Windows PC with a floppy drive and Internet access. Go to http://www.coyotelinux.com and download the Coyote Linux Disk Creator. When you run the program, you'll go through a series of steps to setup the software. You can leave the LAN configuration as it is (unless you want to change the router address). The next step is to setup a login for RoadRunner if that is your ISP. The next step is for the router's Internet connection. The default settings should work for most ISPs. Next, you can enable DHCP service on the router so the machines on the internal network will be configured automatically through the router. The next step is telling Coyote what NICs you will be using. Be sure to double-check your settings. After that, insert a floppy disk and create the boot disk.
Now for the fun part. Boot up the PC with the Coyote disk and when prompted to login, use "root" with no password. A configuration menu will pop up. First, change the root password. Next, you can enable remote access to the router. Opening telnet access to the outside world isn't recommended so you can type this line at the command prompt to only allow internal IP access to port 23:
ipchains -A input -p tcp -d 0.0.0.0/0 23 -i eth1 -j DENY
If you want to run a web server behind the router, you can use port forwarding:
ipmasqadm autofw -A -r tcp 80 80 -h (internal ip of server)
Now you're all set! Documentation and FAQs are available at www.coyotelinux.com