Got permission denied while trying to connect to the Docker daemon socket while executing docker stop

Question

I have 3 containers running on my docker, and I need to stop all of them using the following:

sudo docker stop $(docker ps -q)

When a run the command I got this message:

Got permission denied while trying to connect to the Docker daemon socket at unix:///var/run/docker.sock: Get http://%2Fvar%2Frun%2Fdocker.sock/v1.32/containers/json: dial unix /var/run/docker.sock: connect: permission denied
See 'docker stop --help'.
Usage:  docker stop [OPTIONS] CONTAINER [CONTAINER...]
Stop one or more running containers

I made some search, and the cases that message show does not apply to my environment. I'm using Ubuntu 16.04 LTS with Docker version 17.09.0-ce, build afdb6d4

What does this message mean?

Answer 1

sudo usermod -a -G docker $USER

Reboot then run:

docker container run hello-world

it worked for me on ubuntu 18.2

Answer 2

It seems your user cannot use docker command, so you need to run it via sudo in parentheses as well:

sudo docker stop $(sudo docker ps -q)