2 LAN Cards, Cable Modem

[SitNgrin]

I have a system running XP Pro with 2 LAN cards in it. One is connected to an external cable modem, the other, is going into a Micrsoft Base Station ( MN100 ) router.

The cable modem works great on the hose machine, right up until I enable the other LAN card. Once I enable the LAN card for the router, the cable modem no longer has access to to the internet. Disable the LAN card going to the router, internet works great. Seemingly, when I disable DHCP on the router ( which I thought would work ), the network the router is on can no longer communicate.

Any help whatsoever on this would be greatly appreciated!!

 

[ricpinto]

Can you post the result of ipconfig/all from the command prompt for both of the situation. From there we can start troubleshooting. By the way what's the router purpose in your setup?

 

[SitNgrin]

Thanks for the reply! I will post that once I get home. For now, the reason I am doing it is because I running a game server. The reason is because I am running a game server ( Ultima Online ) on one of the machines. I had the network working perfectly, but for some reason, nobody could ever connect on the game server. I tried port forwarding, making sure that the firewall was down, disabling DNS, nothing seemed to help, so I thought I could bypass the issue by hooking the cable modem directly into the system with the server on it. The server works great, but the network is toast.

 

[ricpinto]

We assume that port forwarding is not gonna work on this game. Try this:

Disable NAT/DCHP on the router.
Internet/ISP/---> WAN port of the router.
Router -> Switch or some router have a built in switch, whatever it is, we'll call it switch1.
Switch1-> game server
Switch1-> firewall with NAT/DHCP--> Switch2 for the network (servers and PCs). Remember to use switches not the dumb hub.

So basically you need 3 public ip address here. one each for router, game server and firewall.

You'll encounter hiccups but post it here so everyone can join the discussion and maybe some have a better idea. Anyone?

 

[ricpinto]

Opps, you're using cable modem which means you've got only 1 public ip. OK,

cable modem-->(nic1)Game server(nic2)-> switch-> network (Servers and PCs).

Nic1-> public ip
Nic2-> private ip


Configure NAT on the Game Server or maybe use third party software like wingate that will take care of NAT and firewall (software). Again you'll encounter hiccups, just post it here.

 

[cadaveca]

the reason you are running into the problem is this...you are in essence bridging the connection from nic to nic and more than likely your isp won't authenticate any device beyond the first connected to modem. when you enable the router you in essence create a backdoor into the isp( your router acts as a dhcp server and no isp that i know of will knowinly give a server an ip). if you really want to get this working the quick and easy way you need to have your router the first thing plugged in to the modem and then run you other machine from it. If you want you can then aasl o connect another router to the first, but then in essence you are becoming an isp yourself.