1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Telling Windows to associate with one NIC and not the other

Discussion in 'Networking Issues' started by techmanblues, Jul 19, 2005.

  1. techmanblues

    techmanblues Network Guru Member

    I have a problem and wonder if any of you have an answer.

    I work in an office that has a 5 static-IPs DSL account. So far, we only use 1 of them, which is the public IP for a NAT router. All the office computers are connected through this router and therefore only use 1 of the 5 IPs. The modem is a Netopia that has 4 ports with one of these used by the NAT router, leaving 3 ports unused. Any computer that is connected to any of these ports will get a static public IP.

    So I decided to make good use of the remaining 4 static public IPs.

    My machine, which is part of the NAT network mentioned earlier, has one NIC and it is configured to obtain its IP (private) automatically from the router's DHCP server. I added a second NIC to this computer and give it a static IP, one of the remaining unused 4 public IPs. This second NIC is connected directly to one of the remaining unsed ports on the Netopia. So basically, my computer has a choice as to how to get out to the Internet: the first NIC behind the NAT router or the second NIC and has a direct connection to the Internet.

    When I start up the computer, Windows XP Pro always use the second NIC to go to the Internet. But how can I tell it to always use the first NIC first before jumping to the second NIC? Or to be more precise, NEVER use the second NIC for connectivity. This is the immediate problem I need to solve.

    The reason I want to do this is I have VMWare on my computer. Therefore I only want VMware to associate itself to the secondf NIC as if the first NIC does not exist. So far, it does that. Since I use VMWare for practicing running a webserver, security for itself is not important right now. However, I do not want Windows to use this second NIC because that would expose it to the Internet directly w/o the protection of NAT as it would be if Windows uses the first NIC.
  2. jgutz20

    jgutz20 Network Guru Member

    Try taking the gateway off of the NIC connected to the router, that way the other NIC should be used to get on the internet, and you can still connect to local computers with the local address on the other card.
  3. techmanblues

    techmanblues Network Guru Member

    But I want both NICs to access the Internet. What I want to do is to make Windows XP Pro use one NIC for one app exclusively. It seems to me that when there 2 NICs that have valid way out to the Internet, XP chooses one at random and ignore the other until reboot.
  4. ReDFlaG

    ReDFlaG Network Guru Member

    may be you should use metrics to weight each nic card.

    go to the properties of your network connection, then tcp/ip protocol of each nic, properties, advanced, desactivate automatic metric and then put the smallest number to the nic you want to be used first.

    i'm not sure this will work but you should give it a try and tell if it's ok or not :wink: (you may have to reboot the pc after having assigning the metrics to each card)

Share This Page