If you want to run docker as non-root user then you need to add it to the docker group.
- Create the docker group if it does not exist
$ sudo groupadd docker
- Add your user to the docker group.
$ sudo usermod -aG docker $USER
- Run the following command or Logout and login again and run (that doesn’t work you may need to reboot your machine first)
$ newgrp docker
- Check if docker can be run without root
$ docker run hello-world
Reboot if still got error
The docker group grants privileges equivalent to the root user. For details on how this impacts security in your system, see Docker Daemon Attack Surface..
Taken from the docker official documentation: