matrix-docker-ansible-deploy/docs/configuring-playbook-prometheus-grafana.md

Enabling metrics and graphs for your Matrix server (optional)

It can be useful to have some (visual) insight into the performance of your homeserver.

You can enable this with the following settings in your configuration file (inventory/host_vars/matrix.<your-domain>/vars.yml):

matrix_prometheus_enabled: true

matrix_prometheus_node_exporter_enabled: true

matrix_grafana_enabled: true

matrix_grafana_anonymous_access: false

# This has no relation to your Matrix user id. It can be any username you'd like.
matrix_grafana_default_admin_user: some_username_chosen_by_you

# Passwords containing special characters may be troublesome.
# Changing the password subsequently won't work.
matrix_grafana_default_admin_password: some_strong_password_chosen_by_you

The dashboards will by default be available on the stats.<your-domain> subdomain, proxied via Nginx.

What does it do?

Name	Description
matrix_prometheus_enabled	Prometheus is a time series database. It holds all the data we're going to talk about.
matrix_prometheus_node_exporter_enabled	Node Exporter is an addon of sorts to Prometheus that collects generic system information such as CPU, memory, filesystem, and even system temperatures
matrix_grafana_enabled	Grafana is the visual component. It shows (on the stats.<your-domain> subdomain) the dashboards with the graphs that we're interested in
matrix_grafana_anonymous_access	By default you need to log in to see graphs. If you want to publicly share your graphs (e.g. when asking for help in #synapse:matrix.org) you'll want to enable this option.
matrix_grafana_default_admin_user matrix_grafana_default_admin_password	By default Grafana creates a user with admin as the username and password. If you feel this is insecure and you want to change it beforehand, you can do that here

Security and privacy

Metrics and resulting graphs can contain a lot of information. This includes system specs but also usage patterns. This applies especially to small personal/family scale homeservers. Someone might be able to figure out when you wake up and go to sleep by looking at the graphs over time. Think about this before enabling anonymous access. And you should really not forget to change your Grafana password.

Most of our docker containers run with limited system access, but the prometheus-node-exporter has access to the host network stack and (readonly) root filesystem. This is required to report on them. If you don't like that, you can set matrix_prometheus_node_exporter_enabled: false (which is actually the default). You will still get Synapse metrics with this container disabled. Both of the dashboards will always be enabled, so you can still look at historical data after disabling either source.

Collecting metrics to an external Prometheus server

If you wish, you could expose homeserver metrics without enabling (installing) Prometheus and Grafana via the playbook.

To do this, you may be interested in the following variables: matrix_synapse_metrics_enabled to true

Name	Description
matrix_synapse_metrics_enabled	Set this to true to make Synapse expose metrics (locally, on the container network)
matrix_nginx_proxy_proxy_synapse_metrics	Set this to true to make matrix-nginx-proxy expose the Synapse metrics at https://matrix.DOMAIN/_synapse/metrics
matrix_nginx_proxy_proxy_synapse_metrics_basic_auth_enabled	Set this to true to password-protect (using HTTP Basic Auth) https://matrix.DOMAIN/_synapse/metrics (the username is always prometheus, the password is defined in matrix_nginx_proxy_proxy_synapse_metrics_basic_auth_key)
matrix_nginx_proxy_proxy_synapse_metrics_basic_auth_key	Set this to a password to use for HTTP Basic Auth for protecting https://matrix.DOMAIN/_synapse/metrics (the username is always prometheus - it's not configurable)

More inforation

• Understanding Synapse Performance Issues Through Grafana Graphs at the Synapse Github Wiki
• The Prometheus scraping rules (we use v2)
• The Synapse Grafana dashboard
• The Node Exporter dashboard (for generic non-synapse performance graphs)