First, if you have any data on your DS6100 you want to keep, back it up. Clean installing an operating system includes wiping your hard drives. We also highly recommend backing up the recovery image in the recovery partition of the DS6100. We have written a guide on how to do this here.
Second, do this at your own risk. Clean installing Windows on your WD Sentinel DS6100 is not something supported by Western Digital. After a clean install on a DS6100, the LCD screen won't work and the system fan will run at full speed. To get these components working, you'll need to install the Windows Essentials Experience role in Windows Server 2012 R2 and the WD components that make them work.
With those things out of the way, let us look at how to perform a clean install of Windows Server 2012 R2 on a WD Sentinel DS6100.
Grab a copy of the Windows Server installation media
Grab a copy of the Marvell 94xx SAS/SATA RAID Controller driver
On a DS6100, go to the directory C:\Windows\System32\DriverStore\FileRepository and copy the files in the folder with the name beginning with mvs94xx.inf_amd64. The four files in this folder contain the driver for the Marvell 94xx SAS/SATA RAID Controller which is used on the DS6100. Copy these files to the directory C:\WorkingDir\mvs94.xx.inf_amd64 on the same computer you have copied your Windows installation media to.
Note that you can use the same files to inject the RAID driver into your Windows PE bootable USB which you will make later in this guide.
Inject the RAID controller driver into the installation media
Run the following three commands to inject the RAID controller driver into the first image (Index:1) inside install.wim.
- Dism /Mount-Image /ImageFile:C:\WorkingDir\Win2012R2\sources\install.wim /Index:1 /MountDir:C:\WorkingDir\mount
- Dism /Image:C:\WorkingDir\mount /Add-Driver /Driver:C:\WorkingDir\mvs94xx.inf_amd64\mvs94xx.inf
- Dism /Unmount-Image /MountDir:C:\WorkingDir\mount /Commit
- Windows Server 2012 R2 Standard (Server Core Installation)
- Windows Server 2012 R2 Standard (Server with a GUI)
- Windows Server 2012 R2 Datacenter (Server Core Installation)
- Windows Server 2012 R2 Datacenter (Server with a GUI)
Create a Windows PE bootable USB and run Windows Setup
Proceed to install Windows as you normally would by following the Windows Setup wizard.