I'm using RH8.0, have recently installed a second network card to my desktop. The network works great except that when the card connected to my local network is turned on i can't make internet work on the server, it's like the first network card gets screwed up.
eth0:192.168.0.100->internet
eth1:192.168.1.1->gateway to local network
Do you have any idea?

Thanks

You probably defined a default route in the setup file for the second NIC, and if you did, that's wrong. You can only have one default route, and it should be pointing to the first NIC (i.e. the one connected to the Internet). The value of the default route, or default gateway should be the IP that your ISP gave you for their gateway.

Also, make sure that the subnet mask for each NIC is 255.255.255.0 (i.e. /24), because if you define the netmask too big it will overlap the other IP on your box.

well i actually did that but it doesn't solve anything. So you're saying that both NIC should have the save default gateway? The thing is that if i boot the first NIC i get internet, then i boot the second NIC the network works but the internet doesn't. To get it back i have to deactivate both cards and reactivate the first one. Does that make sense to you?

interesting now out of nowhere it works... Now how do i get internet access from within the local network? I can access the server from a client.

It's exactly like I told you: You may only have one default gateway, and it must point to the Internet. Don't set a default gateway for the second NIC at all. I don't know if you're using some graphical configuration tool, or directly writing a config file, but you need to not specify a gateway for the 2nd NIC.

Allowing LAN clients to access the Internet through this box is an entirely different matter. You need to turn on IP forwarding and setup a firewall with NAT. There are plenty of descriptions on this board, the Security forum, and many tutorials that are indexed by Google that can tell you how to do this. www.netfilter.org would be a good first step.