Error: Cannot connect to the Docker daemon. Is 'docker -d' running on this host? or Docker dead but pid file exists

[root@pravi~]# sudo service docker status
docker dead but pid file exists

[root@pravi~]# sudo docker run hello-world
Cannot connect to the Docker daemon. Is 'docker -d' running on this host?


Solutions:

I faced the same problem when installing Docker 1.5 on CentOS 7 on Vagrant/VM. Upgrading DevMapper fixed the problem. To do so, run the command:

[root@pravi~]# sudo yum update device-mapper