VirtualBox is a nice piece of software that lets you easily run another operating system (e.g. Windows) from your host system which in my case is Linux at the moment. But for some obscure timer-related reasons, VirtualBox cannot run DragonFlyBSD, the system of my desire, whereas all the other “emulators” like VMware, Qemu or KVM have no problems running DragonFly.

I tried to patch DragonFly to be able to run within VirtualBox, inspired by an idea of someone else. It’s not perfect, but it works. Nevertheless, the rest of this article is about how to migrate from VirtualBox to Kernel Virtual Machine (KVM5).