Nested virtualization not working in guest VM of Win10 running on Win10 host

[1780yz]

On a Win10 physical host with VirtualBox, I installed a VM of Win10, and was trying to enable Hyper-V on the guest VM using nested virtualisation. However, it doesn't work and systeminfo says "Hyper-V Requirements: A hypervisor has been detected. Features required for Hyper-V will not be displayed."

As comparative test, on the same Win10 host with VirtualBox, I installed another VM of Windows Server 2016, and enabled Hyper-V successfully by nested virtualization, and systeminfo says

Code: Select all

Hyper-V Requirements:      VM Monitor Mode Extensions: Yes
                           Virtualization Enabled In Firmware: Yes
                           Second Level Address Translation: No
                           Data Execution Prevention Available: Yes

I've checked the VM of Win10, in context of "Settings > System > Processor", both "PAE/NX" and "Nested VT-x/AMD-V" are enabled. The VirtualBox version is 6.1.

1) Not sure if I missed anything, and any pointers will be highly appreciated.
2) Please also point out if you need me to run a check and provide more information.

Thank you for your help.

[BillG]

I would not expect either of them to work. Nested virtualization is very picky about what systems can be nested, and Hyper-V nested in VirtualBox is not one of the supported options. Hyper-V in Hyper-V is supported (with system limitations).

Have you tried VirtualBox in VirtualBox?

[fth0]

Are you sure that you "enabled Hyper-V successfully"? Because the systeminfo output correctly states that one of the "Hyper-V Requirements" is not fulfilled: "Second Level Address Translation: No".

Iff it was successful, any nested VM will probably run very slooooow.

[1780yz]

Yes, I've just tested, and VirtualBox in VirtualBox works, the setting is: a physical host of Win10 with VirtualBox, installed with a guest VM of Win10; inside the guest VM, install VirtualBox, and then install a guest inside guest of Win10.

It works, but 1) very slow although I've granted 16GB RAM; and 2) the guest inside guest is unable to handle more than 1 virtual CPU. Practically, I feel like to consider other solutions now. But, thank you for your reminder.

Have you tried VirtualBox in VirtualBox?

[1780yz]

You're right that Hyper-V was probably not really working even on Windows Server 2016; and I was just unfamiliar with this part before.

Nested virtualisation is indeed very slow, as described in my other reply. So, practically, I will be looking for other solutions.

My intention is to setup a environment to learn docker, and want to use Docker Desktop for Windows.

My computer has already been installed with VirtualBox, and Docker Desktop for Windows will enable Hyper-V, which makes VirtualBox not working. So I was trying to see if I could do Hyper-V on a guest VM.

Any pointers will be highly appreciated.

Are you sure that you "enabled Hyper-V successfully"? Because the systeminfo output correctly states that one of the "Hyper-V Requirements" is not fulfilled: "Second Level Address Translation: No".

Iff it was successful, any nested VM will probably run very slooooow.

[fth0]

I'd either install Docker Engine natively in a VirtualBox Linux VM (not using Docker Desktop for Windows), or install Docker Desktop for Windows on a Windows host. In the latter case, the Docker containers will run in a somewhat hidden Hyper-V Linux VM anyway.