Am I trying to connect to a TLS-enabled daemon without TLS?

Question

I\'m trying to learn about Docker, but I keep getting cryptic (to me) error messages.

Possibly the simplest example of this is trying to print the version of Docker

Answer 1

1. Docker calls itself a self-sufficient runtime for Linux containers. In simple terms it acts both as server and client.
2. The $ docker version command query is internal to the Docker executable and not to the daemon/service running.
3. $ docker images or $ docker ps or $ docker pull centos are commands which send queries to the docker daemon/service running.
4. Docker by default supports TLS connections to its daemon/service.
5. Only if the user you are logged in as is part of user group docker or you have used sudo before the command, e.g. $ sudo docker images, does it not require TLS connectivity.

Visit Docker documentation page Protect the Docker daemon socket.

Scroll a little to the top and find warning section for clarity.