Before I get into this, it is not a knock on Uptime Kuma. It's a genuinely amazing, easy-to-use piece of software. If you run a homelab or a small fleet and you're not using it, you probably should be. It's free, self-hosted, beautiful, and it does the thing it was built to do better than almost anything else at any price.
There's always a "but," though, so before we get to it I want to spend a little time on what Uptime Kuma does well.
TL;DR:
Uptime Kuma is excellent at telling you when a service becomes unreachable, but it cannot explain why a service is slow or unhealthy while still responding. That requires internal metrics from tools like Prometheus, Grafana, and Alloy. Reachability monitoring and systems monitoring solve different problems, and mature environments typically use both.
Where Uptime Kuma excels
