Configure a nested VM as a host

Nested virtualization is a functionality in Windows Server 2016 and above that allows you to run Hyper-V inside a Hyper-V virtual machine. In other words, with nested virtualization, a Hyper-V host itself can be virtualized. Nested virtualization can be enabled out-of-band by using PowerShell and Hyper-V host configuration.

You can use this functionality to reduce your infrastructure expense for development and test scenarios without the need for individual hardware.

With System Center - Virtual Machine Manager (VMM), you can enable and disable the nested virtualization feature through VMM console. You can configure the nested Virtual Machine (VM) as a host in VMM and perform host operations from VMM, on this VM. For example, VMM dynamic optimization will consider a nested VM host for placement.

Enable the nested virtualization on a VM and then configure it as a host.

Note

Virtualization applications other than Hyper-V aren't supported in Hyper-V virtual machines and are likely to fail. This includes any software that requires hardware virtualization extensions.

Before you start

Ensure the following prerequisites are met:

• A Hyper-V host running Windows Server 2019, Windows Server 2022.
• A Hyper-V VM running Windows Server 2019, Windows Server 2022.
• A Hyper-V VM with configuration version 8.0 or greater.
• An Intel processor with VT-x and EPT technology.

Enable network virtualization

Administrators/delegated administrators can configure nested virtualization by using VMM. Use the following procedures:

• Enable nested virtualization
• Configure the VM as a host in VMM

Enable nested virtualization on an existing virtual machine

1. Identify the VM that meets the above prerequisites.

2. Ensure the VM is in stopped state.

   

3. Browse the selected VM’s Properties.

   

4. On General, select Enable Nested Virtualization.

   

Configure the nested VM as a host

1. Enable the following inbound and outbound firewall rules on the nested VM that you want to configure as the host.

   Inbound Firewall rules

   • File and printer sharing
   • Windows remote management (HTTP-In)
   • Windows management instrumentation

   Outbound Firewall rules

   • File and printer sharing
   • Windows management instrumentation (WMI-Out)

2. Ensure the VM is in running state. Start the VM if it isn't running.

   

3. Right-click the VM and select Configure as a Host. The Add Resource wizard appears.

   

   

4. Run through the wizard, select the options as appropriate, and complete the wizard.

Disable nested virtualization

1. Select the host or VM for which nested virtualization is enabled.

2. Ensure the VM is in stopped state. Stop the VM if it's running.

3. Browse the VM Properties.

4. On General, clear the Enable Nested Virtualization check box.

   Note

   Check the note at the bottom of the wizard page before you disable nested virtualization.

Next steps

Run Hyper-V in a nested VM.