vagrant/website/docs/source/v2/provisioning/docker.html.md

page_title	sidebar_current
Docker - Provisioning	provisioning-docker

Docker Provisioner

Provisioner name: "docker"

The docker provisioner can automatically install Docker, pull Docker containers, and configure certain containers to run on boot.

The docker provisioner is ideal for organizations that are using Docker as a means to distribute things like their application or services. Or, if you're just getting started with Docker, the Docker provisioner provides the easiest possible way to begin using Docker since the provisioner automates installing Docker for you.

As with all provisioners, the Docker provisioner can be used along with all the other provisioners Vagrant has in order to setup your working environment the best way possible. For example, perhaps you use Puppet to install services like databases or web servers but use Docker to house your application runtime. You can use the Puppet provisioner along with the Docker provisioner.

Options

The docker provisioner takes various options. None are required. If no options are required, the Docker provisioner will only install Docker for you (if it isn't already installed).

• images (array) - A list of images to pull using docker pull. You can also use the pull_images function. See the example below this section for more information.

• version (string) - The version of Docker to install. This defaults to "latest" and will install the latest version of Docker.

Pulling Images

The docker provisioner can automatically pull images from the Docker registry for you. There are two ways to specify images to pull. The first is as an array using images:

Vagrant.configure("2") do |config|
  config.vm.provision "docker",
    images: ["ubuntu"]
end

This will cause Vagrant to pull the "ubuntu" image from the registry for you automatically.

The second way to pull images is to use the pull_images function. Each call to pull_images will append the images to be pulled. The images variable, on the other hand, can only be used once.

Additionally, the pull_images function cannot be used with the simple configuration method for provisioners (specifying it all in one line).

Vagrant.configure("2") do |config|
  config.vm.provision "docker" do |d|
    d.pull_images "ubuntu"
    d.pull_images "vagrant"
  end
end

Running Containers

In addition to pulling images, the Docker provisioner can run and start containers for you. This lets you automatically start services as part of vagrant up.

Running containers can only be configured using the Ruby block syntax with the do...end blocks. An example of running a container is shown below:

Vagrant.configure("2") do |config|
  config.vm.provision "docker" do |d|
    d.run "rabbitmq"
  end
end

This will docker run a container with the "rabbitmq" image. In addition to the name, the run method accepts a set of options, all optional:

• image (string) - The image to run. This defaults to the first argument but can also be given here as an option.

• cmd (string) - The command to start within the container. If not specified, then the container's default command will be used, such as the "CMD" command specified in the Dockerfile.

• args (string) - Extra arguments for docker run on the command line. These are raw arguments that are passed directly to Docker.

For example, here is how you would configure Docker to run a container with the Vagrant shared directory mounted inside of it:

Vagrant.configure("2") do |config|
  config.vm.provision "docker" do |d|
    d.run "ubuntu",
      cmd: "bash -l",
      args: "-v '/vagrant:/var/www'"
  end
end

In case you need to run multiple containers based off the same image, you can do so by providing different names and specifying the image parameter to it:

Vagrant.configure("2") do |config|
  config.vm.provision "docker" do |d|
    d.run "db-1", image: "user/mysql"
    d.run "db-2", image: "user/mysql"
  end
end