Docker on bare metal?

Question

On the Docker website I see mention of Docker on "bare metal". Does this mean that you can run Docker on hardware with no underlying OS?

If so, how would one install/implement it?

Answer 1

I do believe that bare metal would most likely represent physical servers that you might have.

Answer 2

Yes, the bare metal in the docs refers to a server that is not in a hypervisor or "cloud server". But running on bare metal.

However if you are interested there has been this experiment as running docker as PID 1 https://github.com/ibuildthecloud/only-docker

Answer 3

Docker, at the time of writing, requires a Linux distribution to run on. From the docs:

To run properly, docker needs the following software to be installed at runtime:

• iptables version 1.4 or later
• Git version 1.7 or later
• procps (or similar provider of a "ps" executable)
• XZ Utils 4.9 or later
• a properly mounted cgroupfs hierarchy (having a single, all-encompassing "cgroup" mount point is not sufficient)

[...]

In general, a 3.8 Linux kernel is the minimum requirement for Docker

Answer 4

It's a bit deceptive but I'm pretty sure they mean that they ship a Ubuntu distro you can install on an unformated (no-OS) computer. Having said that the instructions I found assume you will find and install the OS yourself:

https://docs.docker.com/engine/installation/linux/ubuntu/

It could also simply mean that you don't need VirtualBox installed (bare metal normally refers to the difference between running as a guest OS on a VM and running on a physical box).