synapse/contrib/systemd-with-workers/README.md

Setup Synapse with Workers and Systemd

This is a setup for managing synapse with systemd including support for managing workers. It provides a matrix-synapse, as well as a matrix-synapse-worker@ service for any workers you require. Additionally to group the required services it sets up a matrix.target. You can use this to automatically start any bot- or bridge-services. More on this in Bots and Bridges.

See the folder system for any service and target files.

The folder workers contains an example configuration for the federation_reader worker. Pay special attention to the name of the configuration file. In order to work with the matrix-synapse-worker@.service service, it needs to have the exact same name as the worker app.

This setup expects neither the homeserver nor any workers to fork. Forking is handled by systemd.

Setup

1. Adjust your matrix configs. Make sure that the worker config files have the exact same name as the worker app. Compare matrix-synapse-worker@.service for why. You can find an example worker config in the workers folder. See below for relevant settings in the homeserver.yaml.
2. Copy the *.service and *.target files in system to /etc/systemd/system.
3. systemctl enable matrix-synapse.service this adds the homeserver app to the matrix.target
4. Optional. systemctl enable matrix-synapse-worker@federation_reader.service this adds the federation_reader app to the matrix-synapse.service
5. Optional. Repeat step 4 for any additional workers you require.
6. Optional. Add any bots or bridges by enabling them.
7. Start all matrix related services via systemctl start matrix.target
8. Optional. Enable autostart of all matrix related services on system boot via systemctl enable matrix.target

Usage

After you have setup you can use the following commands to manage your synapse installation:

# Start matrix-synapse, all workers and any enabled bots or bridges.
systemctl start matrix.target

# Restart matrix-synapse and all workers (not necessarily restarting bots
# or bridges, see "Bots and Bridges")
systemctl restart matrix-synapse.service

# Stop matrix-synapse and all workers (not necessarily restarting bots
# or bridges, see "Bots and Bridges")
systemctl stop matrix-synapse.service

# Restart a specific worker (i. e. federation_reader), the homeserver is
# unaffected by this.
systemctl restart matrix-synapse-worker@federation_reader.service

# Add a new worker (assuming all configs are setup already)
systemctl enable matrix-synapse-worker@federation_writer.service
systemctl restart matrix-synapse.service

The Configs

Make sure the worker_app is set in the homeserver.yaml and it does not fork.

worker_app: synapse.app.homeserver 
daemonize: false

None of the workers should fork, as forking is handled by systemd. Hence make sure this is present in all worker config files.

worker_daemonize: false

The config files of all workers are expected to be located in /etc/matrix-synapse/workers. If you want to use a different location you have to edit the provided *.service files accordingly.

Bots and Bridges

Most bots and bridges do not care if the homeserver goes down or is restarted. Depending on the implementation this may crash them though. So look up the docs or ask the community of the specific bridge or bot you want to run to make sure you choose the correct setup.

Whichever configuration you choose, after the setup the following will enable automatically starting (and potentially restarting) your bot/bridge with the matrix.target.

systemctl enable <yourBotOrBridgeName>.service

Note that from an inactive synapse the bots/bridges will only be started with synapse if you start the matrix.target, not if you start the matrix-synapse.service. This is on purpose. Think of matrix-synapse.service as just synapse, but matrix.target being anything matrix related, including synapse and any and all enabled bots and bridges.

Start with synapse but ignore synapse going down

If the bridge can handle shutdowns of the homeserver you'll want to install the service in the matrix.target and optionally add a After=matrix-synapse.service dependency to have the bot/bridge start after synapse on starting everything.

In this case the service file should look like this.

[Unit]
# ...
# Optional, this will only ensure that if you start everything, synapse will
# be started before the bot/bridge will be started.
After=matrix-synapse.service

[Service]
# ...

[Install]
WantedBy=matrix.target

Stop/restart when synapse stops/restarts

If the bridge can't handle shutdowns of the homeserver you'll still want to install the service in the matrix.target but also have to specify the After=matrix-synapse.service and BindsTo=matrix-synapse.service dependencies to have the bot/bridge stop/restart with synapse.

In this case the service file should look like this.

[Unit]
# ...
# Mandatory
After=matrix-synapse.service
BindsTo=matrix-synapse.service

[Service]
# ...

[Install]
WantedBy=matrix.target