VMFS Recovery™
Recover data from damaged or formatted VMFS disks or VMDK files
TRY IT FREEVer 4.27, WinBUY NOWFrom $699
Recover data from damaged or formatted VMFS disks or VMDK files
Last updated: Jun 02, 2025

How to Resize a VHD File and How to Resize VHDX File

Virtual hard disks (VHD/VHDX) are the backbone of virtual machines (VMs) in Hyper-V, acting as their storage containers. Managing their size effectively is crucial for a smooth and optimized virtualization experience. Resizing these files, whether expanding to accommodate growing data or shrinking to reclaim valuable disk space, presents both challenges and significant benefits. This article delves into the methods for resizing both VHD and VHDX files, addressing scenarios such as storage optimization, VM recovery, and general disk management within a Hyper-V environment. Understanding these techniques empowers you to maintain a flexible and efficient virtual infrastructure.

Understanding the VHD and VHDX Formats

VHD (Virtual Hard Disk) and VHDX (Virtual Hard Disk v2) formats are crucial components of Hyper-V environments. Grasping their differences is essential for using them effectively, particularly when it comes to resizing, which is often necessary to accommodate changing storage needs.

What is VHD? VHD (Virtual Hard Disk): As the legacy format, VHD carries certain limitations:

  • Maximum Size: VHDs are restricted to a maximum size of 2TB, which can be a substantial limitation for businesses dealing with large data sets or applications that require extensive storage capacity.
  • Robustness: VHDs are less robust than their successors. This format is more prone to data corruption, especially in scenarios involving abrupt power outages or system crashes.
  • Use Case: Despite its limitations, VHD may still be used in scenarios where backward compatibility with older systems or applications is necessary.

What is a VHDX file? VHDX (Virtual Hard Disk v2): This modern format offers enhanced capabilities:

  • Maximum Size: VHDXs can scale up to 64TB, making them ideal for today's storage-intensive workloads.
  • Resilience: VHDX includes enhanced protection against data corruption, notably through the use of logging mechanisms to recover from unexpected shutdowns. This makes it particularly suitable for mission-critical applications.
  • Features: VHDX improves on performance and scalability with features like larger block sizes and improved alignment, which are particularly beneficial for enterprise-grade environments.

Why Resize?

Resizing VHD and VHDX files can be critical for several reasons:

  • Storage Limitations: As data grows, you may find that your existing virtual hard disk sizes no longer meet your storage needs. Expanding a disk allows you to accommodate more data without needing to provision additional disks or migrate data to larger volumes.
  • Optimization: Reducing the size of a virtual disk after significant data deletion can free up physical storage resources, improving the performance and efficiency of your storage infrastructure.
  • VM Recovery and Migration: Adjusting disk sizes can simplify the process of recovering or migrating VMs by ensuring that they fit within the constraints of the new environment or infrastructure.

Note: When working with virtual machines, the ability to mount VHD files is essential for directly accessing and managing their contents without booting the associated virtual machine. By mounting VHD files in your operating system, you can treat them as physical disks, simplifying tasks such as data transfer, file management, and backup. This process is particularly useful for administrators looking to inspect or recover data from VHDs quickly. Most modern operating systems provide built-in utilities to facilitate the mounting of VHD files, offering a streamlined approach to managing virtual storage needs.

Methods to Resize VHD and VHDX Files in Hyper-V

Resizing virtual hard disks (VHD and VHDX) in Hyper-V can be achieved through various methods, each catering to different needs and user preferences. Below are detailed guides for resizing using Hyper-V Manager and PowerShell Cmdlets.

Using Hyper-V Manager

Hyper-V Manager provides a graphical interface to manage your virtual hard disks. Follow these steps to resize VHD and VHDX files using this tool:

  1. 1. Open Hyper-V Manager: Launch the Hyper-V Manager from your Start menu or search bar.
  2. 2. Navigate to the Virtual Machine’s Settings: In the Hyper-V Manager, locate the virtual machine whose disk you wish to resize. Right-click on the VM and select "Settings" from the context menu.
  3. 3. Select the Disk: In the settings window, navigate to the "Hard Drive" section under the hardware list where your virtual hard disk is attached.
  4. 4. Expand/Shrink its Size: Click on the "Edit" button, which opens the Edit Virtual Hard Disk Wizard. Choose the option to "Expand" or "Shrink" the disk. Enter the new desired size in the appropriate field.
  5. 5. Apply Changes and Resize the Partition in the VM’s OS: Once the virtual disk has been resized, ensure that you also resize the partition within the guest operating system. You can do this through the Disk Management tool in Windows or the equivalent utility in Linux, to utilize the newly allocated space efficiently.

Using PowerShell Cmdlets

For more advanced users or those who prefer command-line operations, PowerShell offers a powerful alternative to resize VHDs and VHDXs. Here’s how you can do it:

  • Expanding a VHD or VHDX: Use the following PowerShell command to increase the size of a VHD or VHDX:

Resize-VHD -Path "C:\PathToFile.vhdx" -SizeBytes 40GB

Replace "C:\PathToFile.vhdx" with the path to your VHD/VHDX file and 40GB with the target size you want.

Shrinking a VHDX: Shrinking is only supported for VHDX files and requires that you first free up unused space within the guest OS. Ensure that you have removed unnecessary data and defragmented the disk in the guest OS.

Use PowerShell:

Resize-VHD -Path "C:\PathToFile.vhdx" -ToMinimumSize

This command resizes the VHDX file to the smallest size possible given the current data content. You can also repair VHD in PowerShell if needed!

By using Hyper-V Manager for a visual approach or PowerShell for command-line proficiency, you can effectively manage the resizing of VHD and VHDX files, enabling you to address storage needs efficiently within your Hyper-V environment.

Note: Understanding how to open VMDK files is crucial for those working with VMware virtual machines, as these files contain the disk data of virtual systems, and it is crucial to fix VMDK if needed. Restoring a VMDK from a flat file is a valuable recovery process when you encounter data corruption or deletion issues within a VMware environment. The flat file, typically named *-flat.vmdk, contains the actual data of the virtual machine's disk. To restore a VMDK from this flat file, you often need to reconstruct the virtual disk descriptor file, which guides the virtualization software on how to interpret the data in the flat file.

Resizing VHD and VHDX Without Hyper-V

In scenarios where using Hyper-V is not an option or when managing virtual disks outside a Hyper-V environment, there are alternative methods to resize VHD and VHDX files. Here, we explore how you can achieve resizing through Disk Management, the Diskpart utility, and third-party tools.

Disk Management

Disk Management offers a straightforward interface to manage your virtual disks within Windows. Here's how you can resize VHD and VHDX files using this built-in tool:

  1. 1. Open Disk Management: Press Win + X and select "Disk Management" from the menu or search for "Disk Management" in the Start menu.
  2. 2. Attach the VHD/VHDX: In Disk Management, click on "Action" in the menu bar and select "Attach VHD." Browse and select the VHD or VHDX file you want to resize.
  3. 3. Expand/Shrink the Virtual Disk: Once the VHD/VHDX is attached, it will appear as a new disk in Disk Management. Right-click on the volume and use the "Extend Volume" or "Shrink Volume" options to adjust its size as needed.
  4. 4. Detach the VHD/VHDX: After resizing, make sure to detach the VHD/VHDX by right-clicking the disk and selecting "Detach VHD" to avoid any disk mishaps.

Diskpart Utility

Diskpart offers a command-line interface for more precise control over disk operations:

  1. 1. Open Command Prompt as Administrator: Search for "Command Prompt" or "cmd" in the Start menu, right-click the icon, and select "Run as administrator."
  2. 2. Run Diskpart Commands:
  • Start the Diskpart tool by entering diskpart in the command prompt.
  • To select the virtual disk, use:

select vdisk file="C:\PathToFile.vhdx"

  • To expand the disk, enter:

expand vdisk maximum=40960

  • Adjust the maximum to reflect the desired size in megabytes.
  • Note that shrinking is not supported in Diskpart. Shrinking requires organizing and freeing space within the file system first.
  1. 3. Detach the Virtual Disk: Ensure you detach the virtual disk using detach vdisk after completing resizing operations.

Third-Party Tools

DiskInternals VMFS Recovery is a specialized VHDX repair tool for Microsoft Windows designed to assist users in recovering data from VMFS (Virtual Machine File System), the file system used by VMware ESXi hosts. Whether due to accidental deletion, hardware failures, or corruption, VMFS Recovery can be an invaluable resource for restoring virtual machine images, VMDKs (Virtual Machine Disk files), and other data stored on these file systems. Here's a closer look at its features and functionalities:

Key Features of DiskInternals VMFS Recovery

  • Comprehensive VMFS Support: DiskInternals VMFS Recovery is compatible with various versions of VMFS, from legacy versions up to the most current. This ensures that you can recover data from a wide range of VMware environments.
  • Advanced Recovery Algorithms: The software utilizes sophisticated algorithms to detect, analyze, and recover inaccessible or lost data. This includes scenarios where the VMFS datastore has been corrupted or damaged.
  • VMDK Recovery: One of the standout features is its ability to recover VMDK files. VMDKs are critical as they contain the virtual machine's disk data. VMFS Recovery can retrieve these files even when the VMFS structure is compromised.
  • Read-Only Access: DiskInternals VMFS Recovery operates in a read-only mode, ensuring that the original data is not altered or further damaged during the recovery process. This protective approach enhances data safety and integrity.
  • Preview Functionality: Users can preview the recoverable files before initiating a full recovery. This feature helps in verifying the integrity and relevance of data, allowing users to selectively recover only what is necessary.
  • User-Friendly Interface: The tool is designed with an intuitive interface that guides users through the recovery process. Even individuals with minimal technical expertise can conduct complex recovery operations efficiently.
  • Remote Recovery: VMFS Recovery supports remote VHD recovery through network connections, which is particularly beneficial for large IT infrastructures or data centers where physical access to hardware may be impractical.
  • Support for Complex Storage Configurations: The software can handle RAID arrays and other complex storage setups, which are common in enterprise VMware deployments, ensuring that even data from failed or degraded arrays can be reconstructed and recovered.

Practical Use Cases

  • Corrupted Datastore: In cases where an ESXi host experiences corruption within a datastore, VMFS Recovery can dig into the depths of the storage medium to retrieve and reconstruct the lost data.
  • Accidental Deletion: If files or VMDKs are accidentally deleted from a VMFS volume, this tool can recover them with ease, restoring critical virtual machine data without the need to rebuild from scratch.
  • VMFS Version Migration: When transitioning from older to newer VMFS versions, VMFS Recovery can ensure that all data is successfully retained and transferred.

Ready to get your data back?

To recover VMware virtual machine, press the FREE DOWNLOAD button below to get the latest version of DiskInternals VMFS Recovery® and begin the step-by-step recovery process. You can preview all recovered files absolutely for FREE. To check the current prices, please press the Get Prices button. If you need any assistance, please feel free to contact Technical Support. The team is here to help you get your data back!

FREE DOWNLOAD Latest version, Win GET PRICES Check now!

Best Practices and Precautions When Resizing VHD/VHDX

Resizing virtual hard disks (VHD/VHDX) is a task that requires careful preparation and attention to detail to ensure data integrity and system stability. Following best practices and taking necessary precautions can help prevent issues and optimize the process. Here are key guidelines to follow when using a VHD or VHDX resizer:

1. Backup Your Virtual Disks

Before beginning the resizing process, it is crucial to create a complete backup of your virtual disks:

  • Data Protection: Backing up your virtual drives ensures that even if something goes wrong during the resizing process, your data remains safe and recoverable. This is a fundamental safeguard against data loss.
  • Backup Methods: Use reliable backup solutions that support virtual environments. Options include creating a copy of the VHD/VHDX file or utilizing backup software designed for virtual machines.

2. Free Up Unused Space Within the Guest OS

Before resizing, particularly if you are downsizing a disk, it is advisable to clean up the guest operating system:

  • Optimize Storage Use: Remove unnecessary files, uninstall unused applications, and empty the recycle bin. This helps to minimize the required disk space and reduces the risk of data fragmentation.
  • Defragmentation: Perform a disk defragmentation if applicable. This can improve the efficiency of the resize operation and ensure that space is reclaimed effectively.

3. Ensure the Virtual Disk Is Not in Use During Resizing

To avoid complications, ensure your virtual disk is not in active use when resizing:

  • Turn Off VMs: Power off any virtual machines associated with the disk to prevent data corruption or conflicts. This ensures all files and data are safely stored and that the disk can be resized without interference.
  • Detach Disks: If you're using methods that require detachment, like the ones involving Disk Management or Diskpart, ensure disks are correctly detached from any active services or applications.

4. Verify Disk Health

Before proceeding with resizing, check the health of the virtual disk:

  • Disk Check: Run utilities like CHKDSK in Windows or alternatives in other operating systems to check for and repair VHD or any disk errors.
  • Integrity Checks: Ensure there are no bad sectors or logical inconsistencies that could impact the resize process.

5. Choose the Correct Resizing Method

Select the right tool or method for your needs:

  • Method Suitability: Whether you’re using Hyper-V Manager, PowerShell, Disk Management, or third-party tools, pick the method that aligns best with your technical capabilities and the specific requirements of your task.
  • Tool Compatibility: Make sure the tool is compatible with VHD or VHDX files, depending on your requirement, and supports the specific operations you need (expand vs. shrink).

Recovering Data from Corrupted or Unmounted Virtual Disks

Virtual disk resizing is generally a smooth process, but various factors can sometimes lead to failures or corruption. Understanding these scenarios and being equipped with reliable recovery tools is essential for safeguarding data. Here we explore potential issues during resizing and introduce DiskInternals VMFS Recovery™ as a robust solution for recovering VHD or VHDX to physical disk.

Scenarios Where Resizing Might Fail or Result in Corruption

Several situations may lead to resizing failures or disk corruption, including:

  • Power Interruption: A sudden power outage during the resizing process can cause incomplete operations, leaving the virtual disk in an unusable state.
  • File System Errors: Pre-existing disk errors or fragmentation issues can interfere with resizing, resulting in unreadable or corrupted data.
  • Software Conflicts: Running other applications or services that access the virtual disk during resizing can create conflicts, leading to errors or corruption.
  • Incorrect Resizing Parameters: Using incorrect size specifications or incompatible tools might damage the virtual disk format.

Given these risks, having a recovery plan using effective tools like DiskInternals VMFS Recovery™ can be invaluable.

DiskInternals VMFS Recovery™: A Reliable Recovery Solution

DiskInternals VMFS Recovery™ is an advanced tool designed to recover data from VMware VMFS systems, addressing both corruption and deletion issues effectively. Its sophisticated algorithms and comprehensive compatibility make it a preferred choice in critical recovery scenarios.

Short Walkthrough of the Recovery Process Using VMFS Recovery™

Recovering data with VMFS Recovery™ involves a few structured steps:

  1. 1. Preparation: Ensure that you have another storage device where the recovered files can be saved, as writing back to the potentially damaged disk is generally discouraged to avoid further data loss.
  2. 2. Installation: Download and install DiskInternals VMFS Recovery™.
  3. 3. Launching the Program: Open DiskInternals VMFS Recovery™. The user-friendly interface will guide you through the setup.
  4. 4. Selecting the Disk: Choose the corrupted or affected virtual disk from which you need to recover data. The software is capable of working with VMFS-formatted datastores, even when the disks are unmounted or have failed to initialize.
  5. 5. Scanning the Disk: Initiate a scan. VMFS Recovery™ will analyze the disk to identify recoverable files, using its advanced algorithms to reconstruct data structures.
  6. 6. Previewing Recoverable Files: Once the scan is complete, the software presents a list of recoverable files. You can preview these to verify their integrity before proceeding with a full recovery.
  7. 7. Recovering the Data: Select the files you wish to recover and specify an alternate location to save them. Initiate the recovery process, and VMFS Recovery™ will safely extract your data without altering or risking the damaged disk's content further.
  8. 8. Validation: After recovering files, validate that the recovered data is complete and uncorrupted. Perform this step to ensure data fidelity and functional usability.

By using DiskInternals VMFS Recovery™, you can mitigate the impact of failed resizing operations or disk corruption, effectively restoring your critical virtual machine data and maintaining operational continuity.

Conclusion

Resizing VHD and VHDX files is a straightforward process when you have the right tools and understanding. Whether using Hyper-V Manager, PowerShell Cmdlets, or alternative methods such as Disk Management and Diskpart, each approach provides a path to effectively manage your virtual storage needs. DiskInternals VMFS Recovery™ also stands out as a crucial tool for restoring virtual machine files from corrupted or unmounted disks, ensuring that your data remains secure even in challenging scenarios.

Proactive storage management is key to preventing emergencies. Regularly monitoring your storage utilization, optimizing virtual disk sizes, and ensuring to backup VHD are essential practices. By staying informed and equipped with the right knowledge and tools, you can maintain a resilient and efficient virtualization environment, capable of supporting your organization's evolving needs securely and efficiently.

Related articles

FREE DOWNLOADVer 4.27, WinBUY NOWFrom $699

Please rate this article.
51 reviews