How may I connect to a docker desktop virtual machine on mac? (docker desktop version 2.4)

Question

On a mac, docker utilizes HyperKit in order to create a LinuxKit VM. This means, for example, among other things, that I cannot see any of the image layers that are pulled down for a given container in places like /var/lib/docker , since the VM controls all of that.

Is there a way to actually get a shell on that VM to be able to do that sort of introspection?

Answer 1

In Docker Desktop 2.4 for Mac, it is possible to get a nearly full terminal into the LinuxKit VM, with sane tab auto-completion, and be able to inspect its contents.

For example, to see the layers of pulled down docker images, you may perform the following commands:

$ stty -echo -icanon && nc -U ~/Library/Containers/com.docker.docker/Data/debug-shell.sock && stty sane
/ # ls -al /var/lib/docker/overlay2/

The nc -U ~/Library/Containers/com.docker.docker/Data/debug-shell.sock may be run on its own, per the Docker release docs , but if it is not combined with stty per the above example, you will not see very good output, nor will you have tab completion in the vm.