Multipass Powered Docker on the Mac

Ever since Docker for Mac began pushing their 'paid platform', I have been looking for a sensible way of removing it from my daily development flow. Plus, the whole filesystem access on Mac, continues to be a bit of a pain and altogether horrifically slow. If this isn't something that bugs you, than likely this small regression when using 'too many' ports will.

WSL2 seems to be a great option for the folks running Windows but, what options is similar to this on the Mac? Apparently Canonical (the folks behind Ubuntu) offer a similar solution titled: Multipass. The best part though? Multipass utilizes OSX's native hypervisor support (hyperkit) for the most performant virtual resource mapping.

Sadly, Multipass is only a virtual machine orchestrator versus a container orchestrator (Docker). However, this ends up being a great happenstance because it means developers can have VM's that are for Docker, Kubernetes, Faasd, the works! With great potential comes a host of configuration. Since these are 'bare virtual machines', there needs to be a way to configure them during their initializations.

Canonical utilizes their tooling called cloud-init to parse metadata and build a repeatable 'image' across virtual machines. Using this, there is a real way to define a Docker specific virtual machine. Afterwards, one can install the docker binary, docker-compose HomeBrew package and set a DOCKER_HOST env var that maps to the cloud-init'ified virtual machine's IP.

With this setup, all containers utilize a 'native' file system access since Docker is running in a Linux environment (akin to the aforementioned: WSL2). This also allows a developer to remove or 'rage delete' the ridiculous Docker Desktop for Mac product. This means removing that horrendous UI, relentless alerts for paid upgrades, and most importantly: the slow filesystem access.

Below is a 'simplified' cloud-init .yaml file for bootstrapping Multipass VMs with Docker already installed.

- docker

- default
- name: dockeradm
groups: users, docker
- ssh-rsa yourPublicSSHKey

package_update: true

- apt-transport-https
- ca-certificates
- curl
- gnupg-agent
- software-properties-common

- curl -fsSL | apt-key add -
- add-apt-repository "deb [arch=$(dpkg --print-architecture)] $(lsb_release -cs) stable"
- apt-get update -y
- apt-get install -y docker-ce docker-ce-cli
- systemctl start docker
- systemctl enable docker

final_message: "The system is finally up, after $UPTIME seconds"

After saving this as docker.yaml, bootstrapping a new VM using Multipass is as easy as the following terminal command:

multipass launch -n docker --cloud-init docker.yaml

Happy VMing!