WSL2 inside VMware Workstation 16 (Nested Virtualization)

[MMirabito]

I am having difficulty in installing WSL2 on Win 10 VM image using Win 10 under the latest version of VM Ware Pro 16.

My host machine has:

• Win 10 Enterprise (21H1 OS Build 19043.1586)
• WSL2
• VMWare Pro 16.2.2
• Docker (4.5.1)

I can run VVM Ware and WSL2 with Docker at the same time.

But now i want to be able to have a win 10 VM image where I install WSL2 and Docker but this is not working for me.

I found this link https://superuser.com/questions/1578372/run-wsl2-inside-vmware-workstation-15 Refering to VM Wware 15 and at the very bottom it says that this no longer possible "Note that as of Feb 2022 you cannot run WSL 2 both in a VMware guest and on the host at the same time"

Am I out of luck? Or is there a trick to do this? If not are there any plans to support WSL on the host and guest and allow for what writer calls "nested virtualization"

Thanks in advance,

max

[wang31894]

Hi All,

I am also very intereted to know if this can be done?  I also need to run docker and WSL on the host and also on a win 10 VM.

Tahnks

[ender_]

WSL2 requires Hyper-V to run. Hyper-V API currently doesn't support nested virtualisation with 3rd party hypervisors (such as VMWare Workstation), so you can't run WSL2 both on the host and inside a VMWare VM.

[MMirabito]

Thank you much for the response do you know if there are any plans to support it  "doesn't support nested virtualization with support nested virtualization with 3rd party hypervisors"

Thanks

max

[MMirabito]

@ender_, Reaching back has there been any change to this limitation?
It's still useful to me to run docker on a Win 10 host but also inside a VM host in VMWare professional 16.x to run isolated experiments. I think this was possible before 16.x but I might be mistaken 

Thanks for any suggestions 

max

[wila]

---

@MMirabito wrote:

@ender_, Reaching back has there been any change to this limitation?
It's still useful to me to run docker on a Win 10 host but also inside a VM host in VMWare professional 16.x to run isolated experiments. I think this was possible before 16.x but I might be mistaken 

---

This is only possible when using the VMware hypervisor, not when Workstation is using the Microsoft Hypervisor API. As you are running docker at the host as well, you're using WHP.

Perhaps it is possible with Workstation Tech Preview (I have my doubts, but it might be worth a try)

--
Wil

[MMirabito]

Hi @wila, @ender_  and All,

While VMWare workstation 16 does not let you do this as you pointed out. 

VMware pro 17 was released but I could not see anything in the notes that addresses nested virtualization  in order to allow me to run Docker desktop both in the host and inside a VMware VM (win 10).

Does anyone know if the limitation is still present in version 17.

Thanks,

max

[Illuminus]

This is a limitation of Hyper-V, not so much of VMWare Workstation. Microsoft has hinted that they're working on enabling nesting for third-party virtualization platforms, but they haven't given a date for it. I suspect that, like the ability to run VMWare and Hyper-V on the same system, it will be a borderline surprise announcement. Watch VirtualBox announcements and release notes for the capability, too. That gave a hint on VMWare's then-coming ability to run on Hyper-V systems.

[MMirabito]

@Illuminus Thank you much for the clarifications.

max 

[famadorian]

Is this still something which is not possible?

I'm running Workstation on GNU/Linux and I want to run Windows 11 with WSL2.

[MMirabito]

Hi @famadorian,

For my use case, I have not been able to get it to work - but it used to work on VMWare 15 😪.

I am on Win 10 Enterprise with VMWare 17.5.1 and I also tried on Win 11 Host the same behavior. Once you turn on virtualization on the VM it does not work if you have virtualization turned on in the Host - at least for me.

But I want to run WSL and Docker simultaneously on my host and VMs and this is where the "nested virtualization" thingy makes it go sideways. 

I followed several suggestions, but I had no luck with nested virtualization support.

An option I found is to turn off the virtualization on the host then VMware images will run, and I can install WSL and use Docker in the VM but at that point I can't run WSL and Docker on the host at the same time.

It's a compromise and I could adjust by temporarily turning off virtualization on the host. But I am concerned of:

• The reconfiguration requires a reboot which is really a hassle IMO. 
• I am unsure if it could permanently break my host configuration forcing me to have to reconfigure WSL and docker on the host the next time to turn it on.  

If you or others have a breakthrough, please share. 

Thanks,

max

[bluefirestorm]

famadorian,

As your host machine is running Linux, you should be able to run WSL2 inside a Windows 11 VM. The issue of the nested virtualisation only affects Workstation Pro 15.5.5 and later running on Windows 10/11 host OS with Hyper-V enabled.

[MMirabito]

@bluefirestorm wow nice I did not know that on Linux host it works. 

Do you know if there is any plan to address: "The issue of the nested virtualisation only affects Workstation Pro 15.5.5 and later running on Windows 10/11 host OS with Hyper-V enabled."

I do not think I am the only one who eagerly awaits a fix.

Thanks,

max

[bluefirestorm]

---

Do you know if there is any plan to address: "The issue of the nested virtualisation only affects Workstation Pro 15.5.5 and later running on Windows 10/11 host OS with Hyper-V enabled."

---

Short Answer:
I don't know. I don't work for VMware and even if I do, I should not be saying anything. But I guess it is likely a limitation of the Microsoft Windows Hypervisor API. So I don't think you should be waiting for a fix to come anytime soon. The problem has been around for 4 years now, longer if you count back to 2017.

Long Answer (with a little bit of history):
The nested virtualisation capability (aka VT-x capability inside VMware VMs) has been around since 2011 (Workstation 8.x on Windows/Linux, Fusion 4.x on macOS and ESXi 5.x).

When Windows 10 1709 was released (the first version that had WSL), Workstation 12.5.x would basically crash when the Windows 10 1709 had WSL installed due to the conflict with Hyper-V. So Workstation 12.5.x, 14.x, 15.0.x users on Windows hosts had to disable WSL/WSL2, Hyper-V, Device Guard, among other things.

When Workstation 15.5.5 was released, Workstation could now co-exist with Hyper-V enabled on a Windows 10 host. The approach was to use Windows Hypervisor API which would run on userspace (presumably ULM means Userspace Level Monitor) instead of making Intel VT-x calls directly at the kernel level (CPL0 means current privilege level 0, which is Intel terminology for running at ring 0/kernel level).

https://blogs.vmware.com/workstation/2020/05/vmware-workstation-now-supports-hyper-v-mode.html

Aside from the performance downside with ULM, nested virtualisation will not work, neither will virtualised performance counters (VPMC). But with CPL0, nested virtualisation works the same way it does since version 8.x plus with all the improvements in Intel VT-x in newer generations of CPUs.

So this problem of "nested virtualisation" does not affect Linux hosts and ESXi hosts at all.

For Fusion on macOS, starting with Big Sur, Apple disallowed the use of macOS kernel extensions and Fusion 12.x had to use the Apple Hypervisor Framework API. On Fusion, the nested virtualisation on Intel Macs was not available for a few months and VMware added nested virtualisation on a minor update.

If you compare the Microsoft Hypervisor API and Apple Hypervisor API online documentation, the Microsoft docs looks quite bare;
https://learn.microsoft.com/en-us/virtualization/api/hypervisor-platform/hypervisor-platform
while the Apple docs you can even see that there is a reference to VMCS Shadowing (which is used in Intel CPUs for better nested VM performance).
https://developer.apple.com/documentation/hypervisor/3182868-hv_vmx_vcpu_set_shadow_access?language=...

Fusion on Apple Mx chips still don't have nested virtualisation though.