Docker host

A Vagrant-based virtual machine to run a Docker CE host.

Installation

Prerequisites

To install this virtual machine you require the following tooling on your host machine:

Git
Vagrant
Virtualbox
Docker CE
Docker Compose
On Windows: Windows Subsystem for Linux with Vagrant installed within WSL.

1. Get the source

Clone this repository to get the configuration of the virtual machine:

git clone git@github.com:nijens/docker-host.git

2. Reference the virtual machine as Docker host

To configure the virtual machine as the default Docker host export the following environment variable:

export DOCKER_HOST=tcp://192.168.33.100:2375

Both the Docker CLI and Docker Compose binaries will listen look at this environment variable. It's recommended to add the above line to the .bashrc file of your user.

3. Build and start the virtual machine

The following command will initialize and start the virtual machine:

vagrant up

Configuration

To customize the virtual machine you're able to create config.yaml file next to the Vagrantfile.

Virtual machine configuration

The following configuration options are available to customize the virtual machine:

# ./config.yaml
cpus:                2              # The number of CPUs attached to the virtual machine.
memory:              3072           # The amount of RAM (in Megabytes) attached to the virtual machine.
ip:                  192.168.33.100 # The IP address of the virtual machine. Please note that this is a private
                                    # network not reachable from the network.
docker_storage_size: 20             # The size (in Gigabytes) of the additional virtual disk added to the virtual
                                    # machine. This virtual disk is used to store all the container images.
                                    # (/var/lib/docker)

To apply the configuration changes, except for the docker_storage_size, run the following command:

vagrant reload

Updating the docker_storage_size requires you to rebuild the virtual machine. This will destroy all the built images and persistent volumes you have created. Although this shouldn't be an issue on a development environment, it's something you should be aware of when applying changes to this configuration option.

To rebuild the virtual machine after a change to docker_storage_size, execute the following commands:

vagrant destroy
vagrant up

Mounting application/project volumes

When developing applications with Docker you need to have your application source accessible for the Docker host. To allow access you're required to configure the path of your application source for the virtual machine.

The following example shows how to configure a directory as volume for the virtual machine and Docker CE without any additional options.

# ./config.yaml
volumes:
    /mnt/c/projects/my-dockerized-application:

To apply the configuration changes, run the following command:

vagrant reload

The configuration of volumes also allows you to change the mount types and mount specific configuration options Vagrant already offers:

# ./config.yaml
volumes:
    /mnt/c/projects/my-dockerized-application:
        type: rsync

For more information about the different mount configuration options, see the Synced Folders chapter within the Vagrant documentation.

Forwarding ports

If you want ports from your local machine (the host) forwarded to the vagrant box (the guest), you can specify this in the configuration file.

Forward a port from your local machine to the same port on the virtualbox, in this example port 8080 is forwarded:

# ./config.yaml
ports:
  - 8080

Forward a port from your local machine to a different port on the virtualbox, in this example port 8080 on the local machine is forwarded to 80 on the virtualbox:

# ./config.yaml
ports:
  - host: 8080
    guest: 80

nijens / docker-host