Nesting on Intel CPU to support docker inside Windows guest on Linux host

[marcwittke]

I just installed the 6.1 beta on my Archlinux

5.3.1-arch1-1-ARCH #1 SMP PREEMPT Sat Sep 21 11:33:49 UTC 2019 x86_64 GNU/Linux

Was thrilled to see my virtual Windows 10 Pro guest being able to install docker, that uses a Hyper-V virtualized Linux under the hood. Also, WSL2 would be intersting, since my guest is insider Build 18970.

However, HyperV MMC is unable to start any machin, WSL2 prompt (ubuntu 18.04) closes immediately. So I uninstalled the Hyper-V feature, rebooted and tried to install it again, but the feature is grayed out:

The tooltip says: "Hyper-V cannot be installed: The processor does not have second level address translation (SLAT) capabilities"

Host CPU is i7-8850H, Virtualbox is configured like this

VT-x/AMD-V
Nested Paging
PAE/NX,
Hyper-V Paravirtualization

So, nested virtualization is not possible using Hyper-V on the guest?

[socratis]

So, nested virtualization is not possible using Hyper-V on the guest?

As a first implementation, only VirtualBox-on-VirtualBox is going to be supported. If anything else works, you're lucky...

[Ramshankar]

The tooltip says: "Hyper-V cannot be installed: The processor does not have second level address translation (SLAT) capabilities"
...
So, nested virtualization is not possible using Hyper-V on the guest?

SLAT (Second-Level address translation) is a synonym for "nested paging" (https://blogs.msdn.microsoft.com/uk_fac ... for-hosts/) .

If the nested hypervisor requires nested paging in order to work you are out of luck currently because the nested paging feature (EPT) of nested-virtualization in VirtualBox has not yet been implemented, i.e. the EPT feature is not passed through to the (outer) guest yet because it is not yet implemented.

[VM-F4n]

Sorry for push this threat....

Does this mean Windows Server 2019 as Guest in VirtualBox 6.1.x and then installing hyper-v (in this guest win server 2k19) don't work?
Bad!
I need Hyper-V inside of Windows Server 2019 for docker (testing)!
This testing i want to make in a VM.

[mpack]

Whether it works or not, it's not supported.