MySQL, PostgreSQL, Redis, Nginx, Apache, Docker, PHP-FPM — when the agent discovers one, the matching plugin attaches itself. No config file, no per-host setup, no exporter sidecars.
MySQL slow-query rate, Redis hit ratio, Nginx upstream timing. None of those are visible from the outside.
A buffer pool sized for the old server explains more than a graph. Both are collected.
A setting you never changed can still be wrong because conf.d or an ALTER SYSTEM changed it. Those are detected, not assumed.
conf.d.pg_settings.INFO. Nginx: stub_status endpoint enabled.All plugins included on every plan.