cfengine3 and puppet both work on FreeBSD, at least. Looks like people are using chef with it too. And, as you point out, Ansible treats it as any other Unix-like system.
I'm not sure what you've tried that does not work!
Ansible and Chef are inadequate tools for the job that cloud server boxes do.
What is needed but is sort of missing:
- A way to run containers. I see that *BSD may have had container-like features (e.g. jails) long before Linux containers existed. The truth us that the prevailing format is Linux-style containers. Ideally one should be able to run ready-made containers in Linux compatibility mode. An ability to build a native container from a Dockerfile is as important.
- An orchestration engine based around containers. Ideally a port of a subset of k8s, but smaller tools the class of Nomad or Docker Swarm would be a good start.
- A good replacement for Docker / Podman / Containerd, preferably with a modicum of compatibility / convertibility from those. You want an easy local development environment.
I bet bits and pieces of it sort of kind of exist, and the kernel is capable enough. Now someone should put (quite) some effort in building that for real, releasing under a reasonable open license, and maintaining it for years.
This is to say nothing of (desktop /laptop) hardware compatibility yet.
Yeah, what Docker (and the ecosystem around it) got right is the user experience, it's just second to none. It just doesn't matter that Illumos zones or BSD jails might be technically better when the user experience of Docker is so much better.
On the smaller end of the scale, docker-compose is fantastic for managing apps if you only have a few systems.
I remember that there of course were efforts to adorn jails / zones with an easy Docker-like UX. I hope this effort continues and will result (or has resulted without me knowing!) in a great and simple developer experience.
Okay, no. If you're going to set the bar at "must be identical to Linux" then you may as well just use Linux. Docker specifically (and anything based on cgroups) is so closely tied to Linux that you're not going to find a clone on a non-Linux platform. Nor should you.
Insofar as encapsulating a container in a file-like format, the primitives are all there: you can export a ZFS snapshot of your jail to a file. Higher level tooling is there as well: iocage has an export subcommand.
Building jails is an exercise left to the reader. I've always found Dockerfiles to be archaic and generally unpleasant to deal with such that I feel like the lack of a Docker compatible template file is a feature not a bug. While I use ansible and some shell scripts, things like Nomad already support (iocage) jails.
I have tried to get cfengine working multiple times, but it's just too difficult compared to every other configuration management solution I can think off.
I'm not sure what you've tried that does not work!