This is a culmination of a number of pieces of trivia I’ve picked up over the years of using FreeBSD on a number of hosts that either don’t support it, or (disappointingly) support it as a second-class operating system. One such host is Online.net, a purveyor of often-astonishingly low-cost dedicated servers. They also run Scaleway, which you may have heard of if you’re into owning VPSs. Online.net supports FreeBSD, but doesn’t support using ZFS on root, which is an extremely popular configuration for FreeBSD servers.
I found out after I went through this process and wrote this post that I could’ve just run
bsdinstall from the FreeBSD rescue system, but I’ve used this exact process elsewhere in places where I don’t have access to
bsdinstall, so while it’s ultimately not as useful with Online.net servers, I’d imagine it’s useful elsewhere, such as one of their competitors who offers products at a higher price and has literally zero FreeBSD support whatsoever.
mfsBSD is one cool set of scripts that allow you to essentially create a tiny bootstrap FreeBSD that weighs about 70-100M and is generally placed right at the start of your disk. There’s a bit to configure here so we’ll walk through it step-by-step.
Unfortunately, this does require a bit of prep. Namely, you kinda need access to an existing FreeBSD system. This can be local, at another provider, or someone else’s computer entirely. I’m fairly sure with enough manual labour you could do this on any system, not just a FreeBSD one, but this is about convenience. Even a FreeBSD liveCD is sufficient.