.VHD File Extension

Virtual PC Virtual Hard Disk

Developer	Microsoft
Popularity	Average rating 4 / 5. Vote count: 108
Category	Disk Image Files
Format	.VHD
Cross Platform	Update Soon

What is an VHD file?

The .VHD (Virtual Hard Disk) file format is a disk image file format that encapsulates the contents and structure of a hard disk drive. It’s primarily used for virtual machines in environments like Microsoft’s Hyper-V and Virtual PC.

More Information.

Initially created for Virtual PC, the .VHD file was meant to simulate a physical hard disk drive’s functionality in a virtual environment.

This allowed users to create, modify, and manage virtual machines with ease, offering a flexible and efficient solution for software testing, system administration, and more.

Origin Of This File.

The .VHD format was originally developed by Connectix for their Virtual PC product, which was later acquired by Microsoft in 2003. Microsoft further developed and integrated the format into their virtualization solutions.

File Structure Technical Specification.

A .VHD file is structured as a hard disk complete with boot data, file systems, and data files. Technically, it includes a footer, dynamic or fixed disk header, and data blocks.

The footer contains information about the disk size, type, and geometry. The header varies depending on whether the disk is dynamic or fixed.

How to Convert the File?

Windows:

Tools: Use Hyper-V Manager, Disk2vhd, or third-party software like StarWind V2V Converter.
Process:

- With Hyper-V, you can convert between VHD and VHDX formats.
- Disk2vhd allows for the conversion of physical disks to VHD.
- StarWind V2V Converter and similar tools offer more format options (e.g., VHD to VMDK for VMware).

Linux:

Tools: QEMU, VirtualBox, and VMware Workstation Player offer command-line and GUI options.
Process:

- QEMU provides a tool called qemu-img to convert between different formats (e.g., qemu-img convert -O raw file.vhd file.img).
- VirtualBox and VMware have their own utilities for format conversion, accessible through their respective command-line interfaces.

Mac:

Tools: Primarily VirtualBox.
Process:

- Use VirtualBox’s VBoxManage command-line utility to convert .VHD files to other formats (e.g., VBoxManage clonehd file.vhd file.vdi –format VDI).

Android:

Tools: Conversion on Android is not typically done due to hardware and software limitations.
Process:

- Instead, use a remote connection to a PC where the conversion can be performed using the above-mentioned tools.

iOS:

Tools: Like Android, direct conversion on iOS devices is not feasible.
Process:

- Use remote desktop applications to access a computer where you can use software like Hyper-V Manager or VirtualBox for conversion.

Advantages And Disadvantages.

Advantages:

Portability: .VHD files encapsulate an entire disk drive in a single file, making it easy to move and copy virtual machines across different physical machines and environments.
Compatibility: The VHD format is widely supported by various virtualization software, including Microsoft Hyper-V, Virtual PC, and even non-Microsoft products like VirtualBox, ensuring broad usability.
Ease of Backup and Recovery: Virtual hard disks can be easily backed up and restored, offering a simple and efficient way to manage data recovery and protection in a virtualized environment.
Snapshots and Differencing Disks: VHD allows for creating snapshots and differencing disks, enabling users to save the state of a virtual machine at a specific point in time and quickly revert if needed.
Disk Management Features: Users can dynamically expand VHD files, compress them, and manage disk space more efficiently compared to physical hard drives.
Safety and Isolation: Operating systems and applications within VHD files are isolated from the host system, reducing the risk of system crashes or malware affecting the primary operating system.

Disadvantages:

Performance Overhead: Virtual hard disks can have slower performance compared to direct physical disk access, particularly in input/output operations, due to the additional layer of abstraction.
Size Limitations: Standard VHD files are limited to 2 TB in size, which can be a limitation for large-scale storage needs.
Increased Complexity: Managing virtual hard disks, especially in environments with numerous virtual machines, can add complexity to system administration.
Risk of Corruption: If a VHD file becomes corrupted, it can potentially affect all the data or systems contained within it, similar to a physical hard disk failure.
Storage Space Requirements: Since VHD files can become quite large, they require substantial storage space, especially when dealing with multiple virtual machines.
Dependency on Host System: The performance and availability of VHD files are directly tied to the performance and stability of the host system and the virtualization software used.

               How to Open VHD?
                  Open In Windows
                  Method: Use built-in tools like Hyper-V Manager (for Hyper-V enabled systems) or Disk Management.
Steps: In Disk Management, you can “Attach VHD” to mount the .VHD file as a drive. Hyper-V Manager is used for managing .VHD files in a virtual machine context.

                  Open In Linux
                  Method: Utilize virtualization software like VirtualBox, QEMU, or VMware Player that supports the VHD format.
Steps: These tools typically involve creating a new virtual machine and selecting the .VHD file as the disk image. For command-line tools like QEMU, you would use specific commands to start a VM with a VHD file.

                  Open In MAC
                  Method: VirtualBox is the most common tool for opening VHD files on macOS.
Steps: Similar to Linux, you create a new virtual machine in VirtualBox and choose the .VHD file as the virtual hard disk.

                  Open In Android
                  Method: Direct opening of .VHD files isn’t typically supported. However, remote virtual machine management apps can be used to interact with systems using VHD.
Steps: Use remote desktop or virtual machine management apps to connect to and manage systems that utilize .VHD files.

                  Open In IOS
                  Method: Similar to Android, iOS does not support direct opening of .VHD files but can use remote management tools.
Steps: Apps for remote desktop or VM management can access and manage .VHD files on servers or desktops from the iOS device.

                  Open in Others
                  Various Other Systems: The method of opening .VHD files depends on the capabilities and software available on the specific platform.
General Approach: Typically, this involves using virtualization software or remote management tools compatible with the system in question. For example, on certain network devices or non-standard operating systems, specific tools or software compatible with VHD might be required.