You can deploy virtual machines in a lot of different ways, using VMWare VSphere, VMWare Workstation, Microsoft HyperV and there are more.
If using VSphere or HyperV you get a real server although it is virtual it acts as a physical server.
With Workstation solutions you still depend on the hosting OS in respect to firewall settings, IP connections and things like that.
So you need to know how to setup Virtual Machines and if setup properly you can run any server application on a virtuel machine.
I usually setup a Windows 2008 Server with one ore more VMWare workstation virtual machines.
On the WIN2008 host server we run VoiceMail Pro and Xima software, and on the Virtual machine we run the Avaya Linux One-X Portal server.
The Linux One-X perform a lot better as the Windows variant,VM Pro on Windows has more features and is easier to debug.
I also have one NIC for Windows and one NIC for the Linux virtual Machine.
I have also done VSphere and HyperV, this is way better as the above but a lot more expensive.
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