How to Increase Disk Size in Hyper-V: The Ultimate Approach

Just as with physical servers, virtual machines (VM) require a large storage capacity to function properly. If your VM starts running low on disk space, the solution is to increase your computer’s storage capacity, which can be done by adding another internal or external hard drive. However, Hyper-V has made this process even easier and faster. To increase your storage capacity, you can increase disk size in Hyper-V in just a few clicks.

In today’s blog post, I am going to walk you through the process of increasing disk size in Hyper-V step-by-step. In a nutshell, to successfully expand a Hyper-V virtual hard disk, you should do the following:

  1. Expand the virtual hard disk using the Edit Virtual Hard Disk Wizard.
  2. Extend the volume size through launching the Disk Management utility inside the VM.

Read further to find out which aspects should be taken into account when you want to increase disk size in Hyper-V and how to protect your virtual infrastructure with NAKIVO Backup & Replication.

How to Increase Disk Size in Hyper-V 

Before you can start the process of expanding a Hyper-V disk, you should note the following:

  • If your VM is running, shut it down. As you know, some settings cannot be modified when the VM is in the running or saved state.
  • The VM should not have any snapshots. After modifying virtual hard disks, the associated snapshots might become invalid.
  • In Hyper-V, you cannot expand disks belonging to a differencing disk chain. Such virtual hard disks have child virtual hard disks associated with them, and any attempt to edit them might result in data loss. Using Hyper-V functionality, you can increase the disk size of only dynamically expanding or fixed virtual hard disks.

If everything is fine, you are ready to start expanding the disks. As mentioned above, this process includes two main steps:

  1. Expand the virtual hard disk using the Edit Virtual Hard Disk Wizard.
  2. Extend the volume size through launching the Disk Management utility inside the VM.

Below, I am going to break down each step separately to avoid confusion.

How to expand Hyper-V VM’s hard disk

The first step of the process is conducted in the following way:

1. Open Hyper-V Manager. Right-click the VM and select Settings.

Opening Hyper-V Manager (Increase Disk Size in Hyper-V)

2. Select Hard Drive in the Hardware pane and click This action will automatically launch the Edit Virtual Hard Disk wizard.

Virtual Hard Drive (Increase Disk Size in Hyper-V)

3. This action automatically launches the Edit Virtual Hard Disk wizard. Click Next to skip the Locate Disk step.

Locate Virtual Hard Disk (Increase Disk Size in Hyper-V)

4. In the Choose Action step, select Expand to expand the storage capacity of the virtual hard disk. Click Next.

Choose Action (Increase Disk Size in Hyper-V)

5. In the Configure Disk step, you can specify by how much you wish to expand the disk.

Configure Disk (Increase Disk Size in Hyper-V)

6. The next step is to look through the changes you are about to implement. Click Finish to complete the action and close the wizard.

Summary (Increase Disk Size in Hyper-V)

To verify that you have succeeded in expanding the capacity of the virtual hard disk, right-click the VM, select Settings, find Hard Drive, and press the Inspect button. This way, you can get access to the virtual hard disk properties and check whether the maximum disk size has actually increased.

Inspect Disk (Increase Disk Size in Hyper-V)

Data Protection with NAKIVO Backup & Replication

Designed for businesses of all sizes, NAKIVO Backup & Replication offers complete data protection for all of your production workloads, including VMware vSphere Backup, Hyper-V Backup, Microsoft 365 Backup and more. Get the Free Trial now!

How to extend the volume inside the VM

The next step is to extend the volume that resides on the virtual hard disk. This operation is performed in the following way:

1. Right-click the VM and select Connect. Start the virtual machine and log in.

Connecting to the VM (Increase Disk Size in Hyper-V)

2. Enter DISKMGMT.MSC in the search bar to open the Disk Management Utility on your VM. Disk Management demonstrates the existing volumes and the amount of unallocated space we would use to extend the C: drive.

Disk Management Utility (Increase Disk Size in Hyper-V)

3.  Right-click the C: drive and select Extend Volume. This action launches the Extend Volume wizard.

Extend Volume (Increase Disk Size in Hyper-V)

4. Select the available amount of space by which you want to extend the volume. Click Next.

Extend Volume Wizard (Increase Disk Size in Hyper-V)

5. Check that you have selected the correct settings. Then, click Finish to close the wizard.

Completing the Wizard (Increase Disk Size in Hyper-V)

As you can see from the screenshot below, the size of the C: drive has successfully increased after extending the volume.

Extended Drive Volume (Increase Disk Size in Hyper-V)

Today's blog post have demonstrated the easiest and fastest way to increase disk size in Hyper-V. Remember to keep track of your Hyper-V storage and avoid the issue of running low on space.

Backup Solution for Hyper-V