Creating virtual disk in the Hyper-V Server

Understanding virtual disk formats

Windows Server 2016 Hyper-V supports two kinds ofVirtual Disk：VHD and VHDX.

VHD

• Maximum support to 2TB
• Compatible with all versions of hyper-v

VHDX

• Only support Windows Server 2012 R2 or later and Windows 8.1 or later
• Maximum support to 64TB
• Support 4KB logical sector
• larger block（Up to 256 MB）

Creating a Virtual Disk

Windows Server 2016 Hyper-V provides several ways to create virtual disk files. You can create them while create a new Virtual Machine. Or you can also create them using the New Virtual Disk Wizard. Or you can create them using Windows PowerShell.

Creating a new virtual disk in Hyper-V Manager

Open Hyper-v Manager, Right-click the Hyper-v Server，Select New | Hard Disk. Or from the Action menu，select New | Hard Disk.

Click Next

Select one of the following disk format options:

VHD: Create a virtual hard disk with less than 2TB and highly compatibility

VHDX: Create a virtual hard disk with greater than 2TB

VHD Set: It's a share Virtual Hard Disk. You can share virtual disk files between multiple virtual machines. Used for failover clustering.

Then Click Next

Select one of the following disk type options：

Fixed Size:The Virtual Hard Disk file size is the same as the Virtual Hard Disk space size. Such as, a Virtual Hard Desk size is 50G，the VHD or VHDX file size is 50G.

Dynamically Expanding: Virtual hard disk file starts small, with more and more data written, virtual hard disk file is also growing, until it reaches the size of the virtual hard disk space.

Differencing: It is a child virtual hard disk file that is associated with a specific parent virtual hard disk file. All system changes will be written to the child virtual hard disk file.

Then Click Next.

Note

It is recommended to use the Fixed Size in production environment. While the Fixed Size allocates all size all at once, waste of disk space, but it provides the best performance.

The Dynamically Expanding while saving space, but their continued growth will have an impact on performance，and also Over-allocation physical disk space.

The Differencing is more suitable for scenes that require frequent return to a certain state of the system.

But it is useful to have Dynamically Expanding and Differencing in test environments

Specify a filename for the Virtual Hard Disk in the Name text box，If necessary, Specify a Non-default location for the file.

Select and configuration one of the following options:

Create A New Blank Virtual Hard Disk: Create a new Virtual Hard Disk and specifie the size.

Copy The Contents Of The Specified Physical Disk: Select one of the physical hard disk in the computer and copy its contents to the new Virtual Hard Disk.

Copy The Contents Of The Specified Virtual Hard Disk: Select an existing Virtual Hard Disk file and copy its contents to the new Virtual Hard Disk.

Then Click Next

Click Finish

Creating a new virtual disk using Windows PowerShell

You can create a new virtual hard disk files using New-VHD cmdlet in Windows PowerShell

Path: The store path of the Virtual Hard Disk

Test.VHDX: The Name and format of the Virtual Hard Disk. The extension name you specify for the filename determines the format（VHD or VHDX） of the virtual disk.

Dynamic: Create a dynamic extended virtual disk.You can use Fixed and Differentiating to create a virtual disk of Fixed size or difference.

SizeByts：Specify size of Virtual Hard Disk 

You can also specify block and logical sector size using BlockSizeBytes and LogicalSectorSizeBytes parameters