A disposable lab for your cursed experiments

Companion repo for Matrix Tutorials #13, this playbook ONLY WORKS FOR DEBIAN.

The Problem

Deploying your setup with containers is a good way to get a rather standard deployment, and avoid a lot of headaches. All taken in isolation it can be tedious to deploy a setup and keep the global picture in mind.

Docker compose is a good way to deploy containers that depend on each other and get a global view of what is happening. It's also often one of the first projects self-hosters interact with to deploy multi-containers applications.

Thib wouldn't recommend docker-compose in a production setup for a variety of reasons. If you're interested in what Thib is personally using and why, you can read My Server Can Burn, My Services Will Run. The short answer is: ansible, podman, and systemd, because he considers that the hardware can catch fire anytime.

Still, docker compose has a huge benefit: it's extremely simple and straightforward to deploy containers with it. But docker and docker compose only address the container part. When you have a fresh server you still need to install the docker engine and docker compose, you need to open the firewall ports… and if your containers rely on configuration files, you need to copy those config files in their respective volumes. This is the case notably for synapse.

This is a particularly salient problem when you want to have a disposable test lab to do awful things, wipe, and start over for a clean state . Fortunately there is a solution to this problem in the name Ansible.

We already used Ansible in the Matrix Tutorial #2, to make use of the very neat matrix-docker-ansible-deploy playbook. The problem we're tackling here is slightly different.

The point is not to use Ansible to deploy your containers, but to use Ansible to put the server in a state where you can run your docker compose file without trouble, with a pre-configured Synapse, database, and reverse proxy. This allows us to then do a lot of fun stuff with the docker compose file, potentially cursed deployments just to test how things work… and then wipe the server and start over very quickly.

How to run this playbook

1. Clone this repo
2. Install ansible on your laptop/workstation
3. Install the community.docker with ansible-galaxy collection install community.docker
4. Update the variables in lab.yml with the values of an already running Synapse's homeserver.yaml and yourdomain.signing.key
5. Update inventory.ini with your host
6. Run ansible-playbook -i inventory.ini -K lab.yml