The system will be built from different components: a daemon (long living process) that runs on each Pi to collect the data, my MQTT server that this data is send to, Home Assistant to save the data and send alarms and Grafana to show some nice stats. Now I am looking to set up a similar system with Home Assistant and make it even better by being able to not just monitor the server itself but also all other Pis I have running. I have run into such a problem back when I was still using OpenHab and have set up a monitoring system back then. It does not change prices for you and allows me to pay for the servers 😉 If you are interested in buying a Raspberry Pi for your smart home consider doing it via my affiliate links above.

Alternatively you can get a kit including everything you need.

Either a LAN cable or if you are not using a newer Pi a seperate Wifi USB dongle. Optional: if you don’t have one yet buy a SD card reader/writer.Optional: a case (with cooling) for the Pi or at least heatsinks.A microSD card, 16+GB from a reliable manufacturer, should be fast: class 10/UHS-1.A USB (C for the Pi 4, Micro USB for the older ones) power supply with around 3.0A.A Raspberry Pi, preferably the Pi 4 with 2 or 4 GB of RAM.As they usually run in headless mode without any display and are hidden somewhere it might take you too much time to notice when they run into any problem. Raspberry Pis are awesome as a low power server, and I am using one myself for my smart home setup.

Instead it is usually a gradual buildup of for example a faulty process that uses more and more resources over time until it crashes the full system. Most of the time the issue that crashes your server in one way or another will not just suddenly happen. If your core smart home server goes down most of your smart home will stop working. Building an alert Keeping an overview – monitoring Raspberry Pis

Grafana internet uptime monitor