Mastodon

Mastodon is a free, open-source social network server based on ActivityPub. Follow friends and discover new ones. Publish anything you want: links, pictures, text, video. All servers of Mastodon are interoperable as a federated network, i.e. users on one server can seamlessly communicate with users from another one. This includes non-Mastodon software that also implements ActivityPub! The easiest way to get started on Mastodon is to join one of the existing servers, but here at OD we're running our own instance which we're documenting here.

Installation

Mastodon has a lot of dependencies that we don't have installed on our server such as PostgreSQL and Ruby, so for us the Docker image is definitely the preferred route, but it's till quite complicated and needs to be done via Docker Compose based on the official installation.

Clone the Docker repo

First, create a mastodon group with number 991 which is used by the project, then create a directory for the persistent data that will be used by the containers (we're putting our repo and data in /var/www/domains along with other web applications - this is not under our document root!), clone the Mastodon Docker repo and checkout the latest stable version.

groupadd -g 991 mastodon
useradd -u 991 -g 991 -c "Mastodon User" -s /usr/bin/nologin -d /var/www/domains/mastodon-data mastodon
mkdir /var/www/domains/mastodon-data
cd /var/www/domains
git clone https://github.com/tootsuite/mastodon.git mastodon-docker
chown -R mastodon:mastodon /var/www/domains/mastodon*
cd mastodon-docker
git checkout $(git tag -l | grep -v 'rc[0-9]*$' | sort -V | tail -n 1)

docker-compose.yml

Before running any docker-compose commands we need to edit the docker-compose.yml file. Change all the images to use the version of the repo you chose above, e.g. "image: tootsuite/mastodon:v2.2.0". Uncomment all the volume path lines for data persistence. The host part (the path before the colon) of each needs to be changed to the absolute data path you set above (in our case /var/www/domains/mastodon-data) instead of just a relative "./path". You may want to enable the elastic search section too. I like to change the restart options from "always" to "unless-stopped" as well.

.env.production

Now copy the .env.production.sample to .env.production and run the setup wizard. Note that most of the questions can be just set as default by entering nothing. Answer "yes" to save the configuration, create the schema and admin user etc.

docker-compose run --rm web bundle exec rake mastodon:setup

Start the instance

Then if all has gone well, you can now run the main Mastodon instance with docker-compose up -d which should give something like the following. To stop the instance use docker-compose down. Note that the docker-compose commands must be run from within the mastodon-docker directory.

# docker-compose up -d
Creating network "mastodon-docker_internal_network" with the default driver
Creating network "mastodon-docker_external_network" with the default driver
Creating mastodon-docker_es_1    ... done
Creating mastodon-docker_redis_1 ... done
Creating mastodon-docker_db_1    ... done
Creating mastodon-docker_sidekiq_1   ... done
Creating mastodon-docker_web_1       ... done
Creating mastodon-docker_streaming_1 ... done

You can now see all the containers running with docker ps which should look something like the following:

CONTAINER ID  IMAGE                                                    COMMAND                 CREATED          STATUS                          PORTS
a67a26fa2b61  tootsuite/mastodon                                       "/sbin/tini -- yarn …"  25 minutes ago   Restarting (1) 47 seconds ago
9b4e6e983c9f  tootsuite/mastodon                                       "/sbin/tini -- bundl…"  25 minutes ago   Up 25 minutes                   3000/tcp, 4000/tcp
52703303a5fd  tootsuite/mastodon:v2.5.2                                "/sbin/tini -- bash …"  25 minutes ago   Up 25 minutes                   127.0.0.1:3000->3000/tcp, 4000/tcp
4f4db81e212b  redis:4.0-alpine                                         "docker-entrypoint.s…"  3 hours ago      Up 3 hours
9887bcc98d49  docker.elastic.co/elasticsearch/elasticsearch-oss:6.1.3  "/usr/local/bin/dock…"  3 hours ago      Restarting (1) 59 seconds ago
63824265d55c  postgres:9.6-alpine                                      "docker-entrypoint.s…"  3 hours ago      Up 3 hours

Connecting with Nginx

Now that we have a running Mastodon instance in a container, we need to connect it to our web-server outside the container. This simply involves creating an appropriate server block to connect request to our Mastodon domain to the ports exposed by the container. I'm basing my server block on this page of the official documentation, see also this excellent guide by Dave Lane.

See also

• Installation on a dedicated server without Docker