Generation 1 virtual machines have capabilities that were previously supported by Windows Server 2012 and other host operating ...

Generation 1 virtual machines have capabilities that were previously supported by Windows Server 2012 and other host operating systems. Generation 2 virtual machines have new capabilities, such as support for the Unified Extensible Firmware Interface (UEFI), and the ability to boot in ways that generation 1 virtual machines could not. For generation 2 virtual machines, the host must run Windows Server 2012 R2.