DHCP - one network card?
 

Do I have to have 2 network cards for a linux box to be connected to the internet and do DHCP for other clients?

Or can you do both with one?

Whats the setup, how do you connect two cables to one card? is their a router, and if so isn't that doing the DHCP?

The linux server is connected to a router doing dhcp.

the reason I ask is becasue I want to setup vpn server on the linux box and I think I may have to turn on dhcp, but I'm not sure.

Either way, I was curious what would happen if I could turn on dhcp with one card and what would happen.

Well with one card not much. The other machines would have to also go through the router to get to your Linux box, which means getting their IP from it.

VPN is used across the internet, not behind a router, as the machines behind the router should act like a lan anyway. The router should already be firewalling your machines.