I have two computers set up, one running XP, and the other running RH 7.3 for a test server. I have hooked the two up to a hub via Cat5 cables and I can acess the files and such on both. But now that I have them connected using the NIC I can not access the internet. Is their a way I can plug the cable modem into the hub and allow internet access for both of the machines?

The ports on the hub are:
Distributed Management Extension
In & Out
12 port hub
ThinLan

Is their a way or would I have to get a router or second NIC?

I guess it depends on the type of modem you are using.
Does it have an Ethernet port?

I was confused at first. Now I think I understand what you are getting at(just removed a sortive long post I wrote.) Are you currently having problems because your cable modem does not support multiple computers, or to be more exact multiple IP's? A cable modem router will solve this, by giving the two computers fake ips then routing the stuff itself. This will cost a little under 90 for retail, or less for ebay(just estimates from my experience). Or the more complicated idea, would be to have one of your computers act as a router(I think you would have your linux box do that). But this would take a little research.

Yes, the Cable Modem has an ethernet port, it is how I am currently getting to the internet.

you can do one of the following

1) call up your cable modem provider - ask for an additional ip, plug cable modem into the UPLINK port of the hub and set up both computers as normal.

2) get another nic - install it in either one of the machines and then setup that machine to share the internet connection. Probly easiest in xp - but more stable with the redhat box. The wiring configuration for this would be.. cable modem to PC1 NIC1 - PC1 NIC 2 to uplink port of hub - PC2 NIC to hub.

3) buy a router - a simple dlink, netgear, or similar device would work...

4) if you've got another computer - build a router - check out smoothwall.org or ipcop.org

Yeap -- Neil hit the nail on the head -- you need some type of Router (running some type of NAT) to share the Internet connection.

If you don't want to use software on one of the PC's, I'd recommend the Linksys Broadband Cable/DSL Router -- $99 at Best Buy. :D