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Everytime I reboot one of my Exchange 2010 CAS servers that are in a CAS Array, the WNLB won't come back up.

I have two Exchange 2010 CAS server configured in a CAS array.  These Exchange 2010 servers are on virtual machines using Hyper-V.  (Windows 2008 SP2)  Everything works fine until I have to reboot one of them.  After I reboot, I'll open the Network Load Balancing Manager and they are not converged.  It won't  even let me ping the NLB NIC anymore after I reboot.  I used the following article (http://support.microsoft.com/kb/953828) and did give the NLB NIC on each CAS Server a static MAC, but this only works until I reboot.  Has anyone experienced problem?  Its caused me so much of a headache that I'm not evening using the CAS array at the moment.  I just have all users pointed to one single CAS Server.  Any help would be greatly appreciated.  Thanks.

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George SasIT EngineerCommented:
When you plan to configure a WNLB array for virtual Exchange 2010 CAS servers that uses Hyper-V Server or Hyper-V Server R2 as the virtualization platform, you can configure the WNLB array in Unicast mode. But you will face an “expected” issue while you configure the WNLB array. The issue occurs because the MAC address of the NIC you use for the WNLB array is changed when you create the WNLB array. This will make the MAC address that Hyper-V assigned to the NIC different from the one originally assigned when you added the NIC under the Hyper-V settings of the virtual machine. To fix this issue, you need to configure a new static MAC address identical to the one assigned to the WNLB (Figure 1). If you are running the virtual Exchange 2010 CAS servers on Hyper-V Server R2, you should tick Enable spoofing of MAC addresses.

Please check the full article here :

I personally dropped teh NLB and I used round robin for a while until we bought a hardware balancer.
MS NLB on a HP switch just sux and will flood the whole network.
denver218Author Commented:
I've configured a static MAC address identical to the on assigned to WNLB, and it does work until I reboot.  Once I reboot the servers won't converge anymore.  I'm about to go to a DNS round robin, I've been dealing with this for months now.
denver218Author Commented:
I also just dropped the WNLB for the CAS Servers.  It was more a pain than anything.  DNS Round Robin is the most painless solution for me at the moment.  
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