for the ignorant, why would I want to wrap docker inside docker?
I haven't used RancherOS but CoreOS works mostly-fine. However, I would avoid using these things altogether because containerization sucks.
What people want is a mainframe where a lump of code is guaranteed to run the same everytime, regardless of the machine state, and if something goes wrong with the underlying layer is self heals(or automatically punts to a new machine, state intact).
What we have currently is a guarantee that the container will run, and once running will be terminated at an unknown time.
Mix in distributed systems(hard) atomic state handling (also hard) and scheduling(can be hard) its not all that fun to be productive for anything other than a basic website.
> it seemed logical and also it would really be bad if somebody did docker rm -f $(docker ps -qa) and deleted the entire OS
or are you asking why anyone would want a 'docker-os', which has everything but the docker daemon as a container?
I saw that line, but since if you want to run docker at scale you'd have each execution node under the tight control of a scheduler, it seemed like a small edge case.
As I said, for the ignorant such as myself why would I chose this over coreos?
I guess this is mostly so you don't accidentally delete OS-containers (like ntpd) when trying to delete all your containers.