I installed it according to docker’s documentation.https://docs.docker.com/linux/step_one/
After the installation is completed, doc’s pspullsearun command will report this error.
Cannot connect to the Docker daemon. Is the docker daemon running on this host?
See on the document let me check
DOCKER_HOSTThis environmental variable, however, I do not know where to check it
I have made similar mistakes.
Because, I forgot to start the docker service.
service docker start