Multiple NICs, Can't connect to 'net, Web servers workfine

I have 3 NICs on one of my servers. Two of them connect to the Internet and handle my web server traffic. The third is a back channel to my local LAN.

Here's the problem...

If the local adapter is connected when the machine boots, I can't get out to the 'net with a browser. The web servers function just fine though!

The adapters, as they appear in Device Manager, are:
- 3Com
- D-Link
- Realtek

The 3Com is the local backchannel and the DLink/Realtek are my web servers.

Any help would be GREATLY appreciated!

4 answers Last reply
More about multiple nics connect servers workfine
  1. What's forwarding your internet traffic on your local lan?

    When one of your computers hits the internet.. is it accessing the internet through the router or is it first going to your Server before it hits the internet?
  2. The two "external" NICs connect directly to the 'net router. The local NIC connects to a 10/100 switch that carries local traffic.

    Additional notes:
    I have a 2nd machine configured identical to this one, same OS, same NICs, etc. I also run Sygate Personal Firewall Pro. on both systems. Both systems are configured to allow the external NICs full access to the 'net, but they are not allowed to access (bridge) traffic on the local NIC.

  3. Do you have forwarding set up via DNS?

    I'm thinking by disabling bridging it would cause the server to act as a forwarded and not let direct access via the internet NICs.

    How exactly are you set up to forward local traffic to the net right now? What are you using?

    DNS forwarders or some other proxy software?
  4. Riser...

    I'm not using DNS locally.

    I have Sygate Personal Firewall Pro installed (too bad they sold out to Symantec... another great product destroyed). It is configured to allow the external NICs to talk to the outside world, but not to the internal NIC and my internal network.

    Again, I have this same configuration on another box, and it runs great.

    Back in the "old days", I would have reassigned IRQs to change the order of the adapters, but with these new fangled PNP systems, I can't readily do that. ;)

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