I'm setting up a mini PC as a Linux learning lab and want to run several virtual machines for practice, possibly including Linux From Scratch later. The machine has an i5 processor with 8 cores, 64 GB of RAM, and 2 TB of storage. I'll use a separate laptop for everyday computing, so the mini PC will mainly host virtual machines. I was considering Lubuntu as the host because it is lightweight, but I'm open to a better choice. I'm also unsure how much RAM, CPU, and storage to assign to each VM. Would allocating roughly 16 GB of RAM to the host and 48 GB to a VM, along with half the CPU cores and storage, be reasonable? Any recommendations for the host operating system, virtualization software, and resource limits would be appreciated.
3 Answers
You could also install distributions directly on separate partitions and use a multiboot setup, especially with 2 TB of storage. However, that means rebooting whenever you want to switch systems and does not give you the flexibility of snapshots, simultaneous guests, or isolated experiments. For a learning lab, VMs are generally more convenient. I’d also favor KVM/QEMU, libvirt, or Proxmox over VirtualBox on a Linux host, since they integrate more naturally with the kernel and are less likely to need fixes after kernel updates.
Proxmox is another strong fit. It is based on Debian and is designed specifically for hosting virtual machines and containers, with a web interface for creating and managing them. It keeps the host focused on virtualization instead of running a full desktop. Start conservatively with resource assignments and leave some RAM and CPU available for the host; you can adjust allocations later as you learn what each VM actually uses.
Since this machine will mainly be a server, I’d use a minimal Debian installation rather than a desktop-oriented distribution such as Lubuntu. Run it headless and use a virtualization platform such as Incus with QEMU/KVM, or another libvirt-based setup. You can create reusable profiles for different guests—for example, a lightweight server might use 2–4 cores, 4–8 GB of RAM, and 20–30 GB of disk, while a desktop VM could use 4–6 cores, 8–12 GB of RAM, and 30–50 GB of disk. Increase those limits only when a particular guest needs it. A bridged network can also let VMs appear as normal devices on your home network.
A headless host is especially convenient here because you can manage the guests remotely and avoid reserving resources for a graphical desktop on the host.