Hi All,

Okay, I am a total newbie with iptables, gateways, and port forwarding, although not a newbie to linux.

What I have:
I currently have a internal network that is protected by a hardware router (cheap one though) that is currently also the Internet gateway for the network. It provides NAT, masquerading, and port forwarding for my web server, sftp server, and remote logins, and is basically setup to serve the network's current needs. The network is a mix of Linux and Win2000.

What I need to do:
I need to install openVPN to connect a remote network to the above network to get them to work as one. I have openVPN installed, but the hardware router will not let me put in static routes, therefore I need to set up a gateway/routing machine to work with the hardware router to allow openVPN operation. I know that I need to build the gateway and have all machines in the network use it for the gateway and then have the gateway forward the packets to their destination, either the openVPN machine if they are intended for the VPN or the router if they are intended for the outside world.

Being non-experienced in routing and gateways, I am stuck on how to get the gateway to do only its thing, no NAT, or port forwarding, or anything like that, and get it to work in conjunction with the hardware router which will be doing its thing.

Any direction or links to guides on setting up a gateway with a separate hardware router would be much appreciated.

I know that the gateway will need two NIC's and that they both will have internal IP addresses, one of which will be the IP address that all internal computers will use as their gateway address, and the other which fill forward the packets to the correct destination. After that I am stuck.

Thanks for any help
mdkelly