How To Install Docker on CentOS 7

Docker is a container-based software framework for automating deployment of applications. “Containers” are encapsulated, lightweight, and portable application modules.

• As of June 2014 Docker has officially released v1.0.0.
• These instructions are intended for installing Docker.
• I’ll be working from a Liquid Web Self Managed CentOS 7 server, and I’ll be logged in as root.

As a matter of best practice we’ll update our packages:

yum -y update

Now let’s install Docker by installing the docker-io package:

yum -y install docker docker-registry

Set the Docker service to start at boot:

systemctl enable docker.service

Then start the Docker service:

systemctl start docker.service

And verify your work by checking the status of Docker:

systemctl status docker.service

Let’s begin using Docker! Download the centos Docker image:

docker pull centos

Now, to setup a basic centos container with a bash shell, we just run one command. docker run will run a command in a new container, -i attaches stdin and stdout, -t allocates a tty, and we’re using the standard fedora container.

docker run -i -t centos /bin/bash

That’s it! You’re now using a bash shell inside of a centos docker container.

To disconnect, or detach, from the shell without exiting use the escape sequence Ctrl-p + Ctrl-q.

There are many community containers already available, which can be found through a search. In the command below I am searching for the keyword centos:

docker search centos