I'm having an issue with a new dual NIC setup. I am very versed in single NIC server setup's and have setup PPTP many times with port forwarding on the router to allow traffic through. My current setup is a new Dell PowerEdge server with Server 2012 Standard. We have two NIC's, one internal and one public.
The internal NIC has a static IP of 10.0.0.10, subnet of 255.0.0.0, no gateway configured. There is an internet gateway on the private network with IP address of 10.0.0.1 that all clients use for internet access.
The public NIC on the server has assigned one of the public routable static IP's assigned by our ISP. The subnet mask, gateway and DNS also all are the settings given to us by the ISP. Since this NIC is connected directly to the public network, I want to setup static packet filters to allow only L2TP traffic through.
This works for the VPN and is secure, however the server has no internet access because it's trying to go out through the public NIC and the static packet filter is blocking it. If I remove the gateway on the public NIC and assign the private NIC a gateway of 10.0.0.1 the server has internet access, but VPN doesn't work.
Is there a secure way to have both?