Docker 101: The Basics
IntroductionDocker is a container-based software framework for automating deployment of applications. “Containers” are encapsulated, lightweight, and portable application modules.
- These instructions are intended for installing Docker.
- I’ll be working from a Liquid Web Core Managed Ubuntu 14.04 LTS server, and I’ll be logged in as root.
Step 1: Installation of DockerFirst, you’ll follow a simple best practice: ensuring the list of available packages is up to date before installing anything new.
apt-get updateLet’s install Docker by installing the docker-io package:
apt-get -y install docker.ioLink and fix paths with the following two commands:
ln -sf /usr/bin/docker.io /usr/local/bin/docker sed -i '$acomplete -F _docker docker' /etc/bash_completion.d/docker.ioFinally, and optionally, let’s configure Docker to start when the server boots:
update-rc.d docker.io defaults
Step 2: Download a Docker ContainerLet’s begin using Docker! Download the fedora Docker image:
docker pull ubuntu
Step 3: Run a Docker ContainerNow, 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/bashThat’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