Windows 2003 Network Load Balancing Question

[200633]

Dear Group,



I have configured Windows 2003 Network Load Balancing for my IIS application. One Cluster IP address and two physical nodes. In each node there is one Network adapter. The NLB cluster configured with multi cast and filtering is set to one. NLB is configured for port 80. The Cluster IP dares has also a hostname configured in DNS.



I noticed when I stop IIS on one node my IIS application works fine.

If I disable a Network Adapter on one node my IIS application doesn't understand it always. Meaning sometimes its running correctly sometimes not. I get a classic error message that my IIS is not reachable.



It looks like NLB sends my IIS requests to the wrong Node because NLB does not understand one NIC is disabled. The NLB cant negotiate sufficient. I'm aware of the heartbeat between the two NLB adapters. It normally takes approximately 6,7 seconds before NLB knows one machine is down.



The question is does NLB understand if I'm disabling a Network Adapter ?



Is there somebody with the same experience with NLB ?



Thanks in advance.



Best Regards,

Shiva

 

[GlenJohnson]

Well, this is a forum for windows 2003 server, but I may be able to help.

I noticed when I stop IIS on one node my IIS application works fine.

Check to see if this nic is sending out bad broadcast packets. It could be going bad. I had the same experience with a 2000 server with 2 nics installed for load balancing. I realized that my clients couldn't access the network at certain times of day. It turned out it was when we were bringing the server up for testing. It wasn't on all the time because it was brand new, and we were still installing it. Good luck.

Glen A. Johnson
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"Maybe this world is another planet's hell."
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[200633]

Dear Glen,

Thanks for your reply.

You mean even if the Nic is down it could sending bad packets ? Anyway its a good idea to analyse this with a network monitor.

Best Regards,

Shiva