vagrant-docker-provider

I'd like to thank rofrano for the code for this project that I was able to use to do my own experimentation. I very much appreciate the open source ethos which I think moves humanity forward in knowledge and collaboration.

This repo will build a docker image that can be used as a provider for Vagrant as a Linux development environment.

As mentioned above, this project was forked from another which included a multi-architecture build and storage of the built container in a remote repository. At the moment I am just wishing to be able to have an amd64 base Docker container that can be used to run Vagrant on a Mac M1. There is a fair bit of the forked project's logic, which I will adjust to fit my use case up over time.

One of my use cases is being able to use Vagrant to run an Intel Docker container under Vagrant. I have determined that this can be done. I accomplished this by adding the architecture as a parameter in the Dockerfile.

FROM --platform=linux/amd64 debian:bullseye

From Vagrant's point of view an image is created. It does not interfere with Vagrant to be hosting an Intel container on an M1 computer. The build does take longer for Intel than for native ARM64. You can change the Dockerfile platform parameter to get an arm container.

FROM --platform=linux/arm64 debian:bullseye

Vagrant with Ansible

I have not used Ansible much but wanted to learn how to use it locally to see how it could be used to provision a server. There is a test in this project that does a simple Ansible package install. I could likely also install python using the raw module but it is easier to have python included with the Docker build then use the apt module. Another option would be to run a playbook that installed python using the raw module then another playbook that used the installed python with the apt module to do the rest of the packages.

Why Vagrant with Docker?

This was inspired by Apple's introduction of the M1 Silicon chip which is ARM based. That means that solutions which use Vagrant and VirtualBox will not work on Apple M1 Silicon because VirtualBox requires an Intel processors. This lead me to find a solution for a virtual development environment that works with ARM and thus Apple M1 computers. To do so a docker provisioner is used.

Docker has introduced Docker Desktop for Apple silicon that runs Docker on Macs that have the Apple M1 chip. By using Docker as a provisioner for Vagrant, we can simulate the same experience as developers using Vagrant with VirtualBox. This is one case where you actually do want a Docker container to behave like a VM.

Image Contents

This image is based on Debian 11 or Ubuntu Focal 20.04 and contains the packages that are needed for a valid vagrant box. This includes the vagrant userid with password-less sudo privileges. It also contains as sshd server. Normally, it is considered a bad idea to run an ssh daemon in a Docker container but in this case, the Docker container is emulating a Virtual Machine (VM) to provide a development environment for vagrant to ssh into, so it makes perfect sense. ;-)

Example Vagrantfile

Here is a sample Vagrantfile that uses this image:

  config.vm.define :server do |cntnr|
      cntnr.vm.synced_folder ".", "/vagrant", disabled: true
      # Configure the Docker provider for Vagrant
      cntnr.vm.provider "docker" do |d| 
        # Specify port mappings, pull value from YAML file
        # If omitted, no ports are mapped!
        # d.ports = container["ports"]

        # Specify a friendly name for the Docker container, pull from YAML file
        d.name = "test-server"
    
        # Set host name
        d.create_args = ["-h", "test-server"]
    
        d.privileged = true
        d.remains_running = true
    
        # Specify the Docker image to use, pull value from YAML file
        d.build_dir = ../../docker
        d.dockerfile = "Dockerfile"
    
        d.has_ssh = true   
        d.volumes = ["/sys/fs/cgroup:/sys/fs/cgroup:ro"]
      end
  end

Task files to run routine opterations

I have included a Taskfile for each test instead of a Makefile. For the purposes of these tests a Taskfile is sufficient and for me more pleasant to read and write. Here are the task commands for the Ansible test

% task -l
task: Available tasks for this project:
* destroy: 	    Destroy vagrant machine
* halt: 	    Halt vagrant
* run: 		    Run vagrant
* ssh: 		    ssh to vagrant
* ssh-config:   Get ssh config
* status:       Vagrant status
* up: 		    Start vagrant

Command Line Usage

To use the docker provider, add the --provider flag to your vagrant command:

vagrant up --provider=docker

This will use this the docker image specified in your Vagrantfile as the base box.

Credits

A huge thanks to Matthew Warman who provided the Dockerfile from mcwarman/vagrant-provider as the bases for my Dockerfile using systemd. He added all the magic to make it work and I am very greateful for his generosity.

imarsman/vagrant-docker-provider