Public and Private IPs on same network?

  bigstu82 01:53 10 Dec 2005


I have an ADSL router (with firewall) which can have a WAN IP and a LAN IP address set. I also have a wireless access point acting as a DHCP server to wireless clients, attached to this router. Also attached (wired) to the router are 2 web servers and a mail server.

Here's my issue:

I only have enough static public IP addresses to assign one to the router, and one to each server.

Wireless clients also need to see the servers, and need to be able to access the internet.

External networks need to be able to individually access the web servers and the mail servers.

Current setup:

WAN IP of router - (one of my static IPs)
LAN IP of router -

The servers each have a distinct static IP, and a distinct private IP on the 192.168.0.x range. Their default gateway is set to - setting it to the static WAN IP of the router doesn't work.

The wireless clients are assigned IPs higher up the 192.168.0.x range by the DHCP on the Wireless Access Point.

All Servers and Wireless clients can access the internet, and all can access each other. The servers cannot, however, be reached by their public static IP addresses, even with the correct firewall configuration; indeed, using one of the servers to browse the web results in the WAN IP of the router being reported as the IP address used - i.e. the router is NATting the requests.

I can't use virtual server/port forwarding to fix this due to my requirements and my client's requirements.

Any ideas?

  mgmcc 13:19 10 Dec 2005

Just a thought but, as I understand it, you have a router and two servers connected to the internet with their own public IP addresses. The servers are inaccessible via the internet because, with your present setup, they are actually going online via the router instead of via their own dedicated access. The wireless clients in the LAN can access all computers, the router, the internet and the servers.

Is there any reason why the two servers need to connect to the computers in the LAN with TCP/IP protocol? In other words, if the servers can use TCP/IP only for connection to the internet, could all of the internal networking between the computers and the servers be done using an alternative "non-internet-compatible" protocol such as IPX/SPX or NetBEUI. That would prevent the servers from having internet access via the router while still maintaining internal network access.

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