Look at Hyper-V

Microsoft Windows Server 2008 Hyper-V allows system administrators to consolidate separate hardware servers on to a single server running Windows Server 2008 as the host operating system. Each of the hosted virtual machine runs in its own separate and isolated virtual environment. This allows to easily manage, provide for, and maintain large numbers of virtual machines while reducing the need to run multiple hardware solutions in order to utilize various products and operating systems.
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