Notes on how to create a virtual machine on Windows 8.1 and install SQL Server on it

1. It needs Window 8 Professional edition. Hyper-V is included as an add-in in Windows 8 Professional.
2. Generation 2 does not work for me on Win 8.1 Professional. Generation 1 works!
3. After the installation, do not need the .iso file on the virtual DVD anymore. Choose None for the DVD after the installation.
4. If you need an Internet connection for the VM, create an external virtual switch.