Virtualization serves as the crux of pretty much every home lab project, be it running an instance of macOS on top of your favorite hypervisor or testing new Linux distros for your self-hosting needs. However, nested virtualization dials the whole running-a-PC-inside-a-PC shtick to an eleven, as it lets you turn virtual machines into hubs capable of deploying their own VMs.

On paper, it sounds like a weird feature with non-existent real-world applications. However, there are plenty of reasons to go out of your way to enable nested virtualization, regardless of whether you’re into self-hosting a few essential services or a home lab enthusiast running a behemoth Xeon server with tons of cores and insane amounts of memory.

3 Run Docker Desktop inside VMs

Especially useful when you’re just starting out

Most containerization experts would recommend using a CLI-based approach when deploying apps and services using Docker. However, memorizing terminal commands can be a little complex for newcomers to the Linux space. Thankfully, the Docker Desktop's menu-based approach can ease most beginners into the fine art of self-hosting.

While the normal versions of Docker Engine and Docker Build work fine, Docker Desktop will throw an error if you try to run it inside a virtual machine without enabling nested virtualization. But once you turn on nested virtualization, the app works fine without any hiccups.

2 Try out other hypervisors

A solid learning experience for aspiring sysadmins

Whether you’ve built your home lab using VMware Workstation Pro or chosen a bare-metal virtualization platform, there may come a time when you may need to utilize another hypervisor. If you wish to migrate to a different hypervisor, this neat feature can help you familiarize yourself with the new platform. Perhaps you just want to see whether TrueNAS Scale supports all the self-hosted apps you’ll ever need. Or maybe you're a curious soul who wants an easy way to test home lab operating systems without spending money on additional hardware.

Thanks to nested virtualization, it’s possible to turn your home lab into a hypervisor testing ground. Assuming you’ve allocated sufficient cores and memory to the hypervisor VM, you shouldn't encounter performance issues in your virtualization experiments, either! While we’re on the subject of experimenting…

1 Build a foolproof home lab testing ground

… Inside your actual home lab

Home labs, by their very nature, are environments where you’re free to tweak, test, and break operating systems, apps, and even the hypervisor’s settings… Or so you’d believe for the first couple of months. But once you’ve created your ideal home server, you’ll be a lot more hesitant to mess around with it, as one false mistake could force you to start from scratch.

Since you can deploy a home lab on top of your working instance using nested virtualization servers, you won’t have to worry about accidentally damaging your actual server in your experiments. Take it from me, being able to tweak any setting on your virtualized instance of a home lab and re-deploying it from the actual server when things go wrong feels cathartic.

Home labs and nested virtualization are a killer duo for hardcore tinkerers

As someone who earns his daily bread by conducting insane experiments with tech, nested virtualization is a staple part of my home server. I mostly use it with Proxmox, where the facility works incredibly well when I want to assess the impact of certain network and security settings before replicating the changes on my current self-hosted lab. However, most hypervisors (including those belonging to the Type-2 faction) support nested virtualization in some shape or form. So long as you have a relatively modern processor, you should be able to set up this facility in no time!