`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
## More information
- [Understanding Synapse Performance Issues Through Grafana Graphs](https://github.com/matrix-org/synapse/wiki/Understanding-Synapse-Performance-Issues-Through-Grafana-Graphs) at the Synapse Github Wiki
- [The Prometheus scraping rules](https://github.com/matrix-org/synapse/tree/master/contrib/prometheus) (we use v2)