Exploring Proxmox on Windows 11: A Nested Virtualization Experiment

What do you get when you mix a bare-metal virtualization platform with the comforting embrace of Windows 11? An interesting exercise in creativity and frustration! Recently, a daring enthusiast decided to run a Proxmox virtual environment on top of their existing Windows 11 installation, and they documented the entire exploratory journey that promises to entertain home lab enthusiasts and those looking to push their system to the limits.

The Experiment Begins​

A few months back, many tech-savvy individuals would likely agree that building a server with a Type-1 hypervisor is the gold standard. Why? Because it’s a smooth ride when it comes to device passthrough, especially with PCIe devices, and you skip the headache of an underlying operating system, which often saps performance. But let's be real—we all enjoy a little chaos from time to time.
This DIY tinkerer chose VirtualBox as their Type-2 hypervisor of choice after considering other options like Hyper-V. Why not Hyper-V, you ask? Well, it’s often considered a Type-1 hypervisor, and our protagonist was eager to dance on the edge with the Type-2 flavor. Armed with their trusty 6-core Ryzen 5 5600X and a generous 32GB of RAM, they embarked on configuring Proxmox on their Windows machine—after all, it is where their encounter with the quirks of nested virtualization would begin.

Setting Up Nested Virtualization​

Activating nested virtualization is the crux of the experiment. What is nested virtualization, you wonder? Imagine running a virtual machine (VM) inside another VM—it's like building a house within a house! However, just like many DIY projects, this came with a few hiccups. Initially, the option to enable nested virtualization within VirtualBox was grayed out. Fortunately, a bit of sleuthing led to a breakthrough via the Windows terminal, needing only a simple command:
With this command, the tinkerer enabled support for nested hardware virtualization, and their journey continued.

The Dance of Errors and Adjustments​

After launching their Proxmox VM, things took a turn when it failed to detect hardware-accelerated KVM virtualization (Kernel-based Virtual Machine). No worries, as is typical of tech projects, troubleshooting ensued. The tinkerer dove into settings, finding that Windows Hypervisor Platform features were the main culprit. A quick disable in the Control Panel led to Ubuntu finally being deployed successfully inside the Proxmox VM.
Here’s a quick checklist of what they adjusted to smoothen operations:

• Nested virtualization toggling: Ensured proper activation.
• Network settings: Changed to Bridged Adapter to access the Proxmox web UI conveniently.
• KVM features: Enabled in the Acceleration tab, smoothening the KVM experience.

Running Multiple VMs - An Unholy Alliance​

Once the Ubuntu environment was stable, the tinkerer couldn't resist the urge to push boundaries. They created additional virtual machines using different Linux distros—Debian, OpenMediaVault, and Elementary OS—running a mini server farm all within a virtualized Proxmox setup. While the performance was not horrendous, it was certainly slower than expected, proving that running VMs inside a VM has hefty ramifications on responsiveness.
What's a home lab experiment without some chaos? In a moment of pure adventurous folly, our protagonist even attempted to spin up another Proxmox VM inside the already virtualized Proxmox environment. Spoiler alert: it didn’t work out, but it was certainly a testimony to the lengths we go to just to tinker with technology!

Should You Follow Suit?​

Now that the dust has settled, the intention behind this experiment shines through. While this setup could theoretically be replicated for educational purposes or to dabble in hypervisor testing, it's not recommended for serious home server projects. The overhead of running Windows 11 as your base OS creates challenges that even the most prepared techie might struggle with.

Key Takeaways:​

• System requirements: Always ensure your hardware is equipped to handle such projects. Adequate RAM, CPU cores, and disk space are no joke!
• Performance limitations: Expect overhead if you decide to run a hypervisor inside another OS.
• Feasibility: Consider if this setup aligns with your performance needs. Some projects require direct control over hardware, making bare-metal installations more attractive.

Conclusion: A Learning Experience​

In conclusion, while building a Proxmox home lab inside Windows 11 sounds like an alluring challenge for budding tech enthusiasts, it’s better suited for those who thrive on troubleshooting and tinkering. Next time you get the urge to experiment, remember this adventure—embrace the chaos, but don't forget to plan for the inevitable hurdles that come with it.
Whether you’re an experienced server guru or a novice eager to experiment, remember: the tinkering mindset is as valuable as the technology. Keep pushing those boundaries, and who knows what you’ll discover next!

---

Source: XDA I tried building a Proxmox home lab... inside Windows 11