see possible solution at https://forums.docker.com/t/cannot-connect-to-the-docker-daemon-is-the-docker-daemon-running-on-this-host/8925/3
After the installation finishes, Docker usually starts up on its own, but for the next part to work you will need to stop it.
sudo service docker stop
Then run the daemon with the following command:
sudo nohup docker daemon -H tcp://0.0.0.0:2375 -H unix:///var/run/docker.sock &
The script leaves the daemon running in the background, and with the Docker ready you can test that it is accepting commands.
sudo docker info
To make working with Docker easie