Dual NIC question, sharing internet

[pr1mal0ne]

I am wanting to share my computers internet access to another computer through a network cable. My Computer with internet access(host) has two NICS (one onboard one card). So my question is how do i set it up so that one NIC accesses my WAN and the other NIC just functions to give my client computer an IP and access to the internet.
I am aware that this is what a router is for, but for reasons outside my control, I can not use one.

The host computer boots XP, WIn7, and Ubuntu, although I would like to have this done in XP mainly.

 

[Emerald]

Start > All Programs > Accessories > Communications

Network Setup Wizard will allow you to connect a computer to a computer that has access to the internet

 

[pr1mal0ne]

Ya but the problem is coming a step before that. I cant seem to get my secondary NIC to DHCP for the client computer. It doesn't see that computer at all. I feel confident that once my host computer is giving an IP address to my client that sharing that internet from the other NIC shouldn't be a problem.

 

[Emerald]

It should DHCP once you finished going through the Network Setup Wizard.

are you using a crossover cable to connect the two computer?

 

[pr1mal0ne]

Ya its a crossover. So your saying that before network setup wizard i dont have to do anything besides plug cables in and afterwards it will all be working.

 

[eibgrad]

Perhaps this is obvious, but you need to enable ICS (Internet Connection Services) in order for this to work. Perhaps you have, but since no one has mentioned it, I thought I would. It's ICS that establishes the DHCP server for your client(s)!

Using ICS, the WAN NIC is transparently bridged to the local NIC where your clients reside. By default (iirc), ICS sets up a static IP for the local NIC of 192.168.0.1, then using DHCP, assigns additional IPs in the same 192.168.0.x network when those clients make their DHCP requests. As long as you enable ICS and connect the right cables to the right NICs, it all pretty much just works.

And btw, you rarely need crossover cables anymore. Unless you’re dealing w/ very old networking devices, almost all now support auto-mdix, which automatically configures the ethernet cabling correctly. So you can use standard ethernet cabling in almost all cases.