I've wanted to run *NIX on my Compaq Deskpro 386s/20n and I've just stumbled across the perfect distribution for it. Turns out that, back in teh mid-90s, a bunch of developers created 386BSD based on 4.3 BSD. The source of 386BSD 2.0 has recently been released and is now available via the 386BSD github repo.
I'm not overly confident with raw *NIX systems, and so was hoping for a boot disk/installer scenario and it seems that this is provided. Below are my feeble attempts to get it going.
Creating a boot disk on Windows 10
For most of the following, I've used the instructions found here at gunkies.org for getting 386BSD running on Qemu. I downloaded rawwritewin. dist.fs was written to the disk, but it failed in every system I tried it in. Turns out it's a 1.2mb image and not a 1.44mb image. Somehow the tracks/sectors of the floppy are written into the image and incompatible when you write them to a disk of differing geometry.
I then searched, trying to work out how to convert a disk image from 1.2mb to 1.44mb. The link above just pads out the image file with zeros... but this can't be correct? Seems that QEMU will happily boot that though? I then came across this link which uses ImageEdit to convert a 1.2mb image to an IMD. This app doesn't run on Windows 10, so I booted up my Win98se VM and ran it there. An IMD was produced, but this had the same issues on all disk writing applications I tried. You can download ImageEdit here if you need a copy of it.
Using someone else's bootdisk
There's another article at gunkies.org titled Installing 386BSD 1.0 on Qemu. Turns out this has a downloadable disk image in 1.44mb format. There's two images at the top of the article. 5boot.img seems to be corrupt. ddbboot.img is actually a DOS bootdisk that contains the 386BSD kernel in DDB format and uses boot.exe to kick it in to gear.
I booted the latter and ran boot 386BSD.ddb wd1d and nothing... it reads for a bit but just stalls... I wonder if my poor 386 is insufficient with only 2mb of RAM? It has already loaded in to DOS, so there's probably hardly any RAM left and hasn't got a chance to then boot further? The other issue is that wd1d is a hardware device which might only be valid for Qemu?
I'll dig further and see if I can get this working... stay tuned...