Survey: Extend / Expand Microsoft Hyper-V VHD
Before you begin, create a backup copy of the virtual disk so that you can restore it in case of failures. Extending a virtual disk can be a complex operations for several reasons, e.g.,:
- The virtual disk that is full happens to contain the boot/primary partition for Windows
- There are snapshots
- There is insufficient disk space available on the physical drive to permit growth
- It is a multi step process and involves use of different tools and commands in a specific sequence.
You’ll find several posts regarding this topic on Google. Essentially, they are all variations of the following posts:
- Tutorial to extend boot/system partition using EASEUS Partition Master for dynamic and fixed VHD’s
- VHD Utility can be used for extending file system partitions for dynamic and fixed VHD’s.
- Microsoft is offering a free VHD tool, including its source code, which is an unmanaged code command-line tool that provides useful functions, e.g.,
- Tutorial for resizing a virtual disk using VHD Resizer
- Expanding Virtual Hard Disks with Hyper-V
Create a new 10 GB fixed VHD:
VhdTool.exe /create "c:\Program Files\MyApp\foo.vhd" 10737418240
Convert an existing flat image file into a VHD & do not output status to the command line.
VhdTool.exe /convert bar.img /quiet
Extend an existing fixed format VHD to a larger size.
VhdTool.exe /extend foo.vhd 21474836480
Repair a Hyper-V snapshot chain broken by expanding the base VHD.
VhdTool.exe /repair base.vhd base_EF2F9402-E85B-402F-A979-631CB287C2C4.avhd