How to Install Docker on Ubuntu 15.04

Introduction

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

Pre-Flight Check

• These instructions are intended for installing Docker.
• I’ll be working from a Liquid Web Self Managed Ubuntu 15.04 server, and I’ll be logged in as root.

Step 1: Installation of Docker

First, you’ll follow a simple best practice: ensuring the list of available packages is up to date before installing anything new.

apt-get update

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

apt-get -y install docker.io

Then, and optionally, let’s configure Docker to start when the server boots:

update-rc.d docker defaults

And then we’ll start the docker service:

service docker start

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

docker pull ubuntu

Step 3: Run a Docker Container

Now, to setup a basic ubuntu 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 ubuntu container.

docker run -i -t ubuntu /bin/bash

That’s it! You’re now using a bash shell inside of a ubuntu 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 debian:

docker search debian