$ uname -r3.10.0-229.el7.x86_64

$ sudo yum update

$ sudo tee /etc/yum.repos.d/docker.repo <<-‘EOF‘[dockerrepo]name=Docker Repositorybaseurl=https://yum.dockerproject.org/repo/main/centos/$releasever/enabled=1gpgcheck=1gpgkey=https://yum.dockerproject.org/gpgEOF

$ sudo yum install docker-engine

$ sudo service docker start

$ sudo docker run hello-worldUnable to find image ‘hello-world:latest‘ locally    latest: Pulling from hello-world    a8219747be10: Pull complete    91c95931e552: Already exists    hello-world:latest: The image you are pulling has been verified. Important: image verification is a tech preview feature and should not be relied on to provide security.    Digest: sha256:aa03e5d0d5553b4c3473e89c8619cf79df368babd1.7.1cf5daeb82aab55838d    Status: Downloaded newer image for hello-world:latest    Hello from Docker.    This message shows that your installation appears to be working correctly.    To generate this message, Docker took the following steps:     1. The Docker client contacted the Docker daemon.     2. The Docker daemon pulled the "hello-world" image from the Docker Hub.            (Assuming it was not already locally available.)     3. The Docker daemon created a new container from that image which runs the            executable that produces the output you are currently reading.     4. The Docker daemon streamed that output to the Docker client, which sent it            to your terminal.    To try something more ambitious, you can run an Ubuntu container with:     $ docker run -it ubuntu bash    For more examples and ideas, visit:     http://docs.docker.com/userguide/

$ sudo chkconfig docker on

$ yum list installed | grep dockeryum list installed | grep dockerdocker-engine.x86_64   1.7.1-1.el7 @/docker-engine-1.7.1-1.el7.x86_64.rpm

$ sudo yum - y remove docker-engine.x86_64

$ rum -rf /var/lib/docker