This post discusses the proper way to make a configuration change to a highly available virtual machine in a Windows Server 2008 Failover Cluster. I will demonstrate how to add a Pass-through disk to a highly available virtual machine by attaching it to a SCSI Controller. You can also use an IDE controller, but I chose to use a SCSI controller because it is not available by default and as we walk through the process, you get the added benefit of seeing how to add it (Note: SCSI controllers require the installation of Integration Components in the Guest). Please keep in mind that this process will not be supported in a Windows Server 2008 R2 (download) Failover Cluster using cluster Shared Volumes (CSV).

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