Do I need 2 network card and 2 fixed IP address to set up a VPN server?

Posted on 2004-11-08
Last Modified: 2010-04-12
When I set up my VPN server on Windows 2003 Server, it said I need to have 2 network cards.  Ok, I installed another network card and configured the VPN server.  I have a fixed IP in my office and the Netscreen firewall is between the VPN server and the internet.  The firewall use the IP of and the server has to use inorder to work with Netscreen firewall.  Do I need to type in my real IP for the network cards? Right now, I have it on auto.  If I type in the real IP then it will have conflict with the firewall setup.  Also, I have 2 network cards, so I need 2 fixed IP for the 2 network cards?  I am really confused!  What is the proper procedure to set up a VPN.  I have checked the Microsoft documentation and it's not covered.

Thanks for the help in advance!
Question by:rickyfung
    LVL 7

    Accepted Solution

    No, you don't need two NICs if you have a router or firewall. this may help. quoted from

    How to setup VPN on w2k server with one NIC

    Symptoms: When attempting to create VPN on w2k server with one NIC, you may receive "You have chosen the last available connection as the Internet connection. A VPN server required that one connection be used as the private network connection" if you select the NIC.

    1. You should highlight No internet connection instead of the NIC or LAN connection.
    2. You may try "Manually configured server option".

    LVL 6

    Assisted Solution


    internet  <->   router  <->  sub net <->  Vpn server


    That will work ok, but because you don't have real internet ip on the server you will need to have your router do port forwarding

    port 1723  

    Author Comment

    As you know I have a Netscreen firewall and the ports opened are 21,23,25,110,80.  Can I use one of these ports instead of 1723 ?  Can I configure this in the VPN Server?
    LVL 7

    Expert Comment


    Author Comment

    So, how do I configure the VPN to use let say port 25 instead of 1723?

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