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We have a performance test environment that we built to run load testing on. We have a presentation tier and an application tier each made up of 4 servers, with a sql server feeding these.

We are using Windows Load Balancing on Windows 2003 Server (Enterprise).

The issue I have is that the most of the time, during a test, about 80% or more (sometimes 100%) of the work is done by only one of the servers in the cluster.

Cluster operating mode:

  • List item
  • Unicast
  • The host Port rules are:
  • Protocols: TCP
  • Filtering mode: Multiple host
  • Affinity: None
  • Load weight: equal.

What am I doing wrong?

Update: 16/09/2010 Thanks for the info Bart Silverstrim. I think what I am doing wrong is the fact that in our performance test environment, for the specific test that I am running, I only have a single client.

Is there any way that I could set up Windows Load Balancing on Windows Server 2003 to still balance the load while using only a single client? Basically, I just need it to round-robin.



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According to the NLB Fundamentals FAQ ( ) it doesn't balance CPU or memory usage, but rather network load and availability (kill a server, another one takes over).

Maybe that's what you're running into?

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