Pyssel

Having some Linux servers up and running I checked out  monitoring tools like Nagios, Zabbix, Cockpit or Prometheus. For small setups, home labs, or lightweight environments, those solutions can feel like using a sledgehammer to crack a nut. In this post, I’ll show you how to build a   lightweight monitoring agent   using nothing more than a Bash script, MQTT, and Node-RED. The script collects key metrics from your server — disk usage, memory consumption, CPU load, and available package upgrades — then publishes them to an MQTT broker. From there, Node-RED visualizes the data in a clean, real-time dashboard. The result? A simple but powerful monitoring system that works across multiple servers, scales with your needs, and gives you instant visibility into the health of your infrastructure. And the best part: you control every piece of it.

Updated 2025-09-08 ! A fantastic way to distribute data between devices is using MQTT . In this post I will do a quick and simple setup with Node-Red(NR) and the Mosquitto(MQ) broker on a Linux machine. Very short, the Broker , installed on a server, handles incoming Publishing and Subscriptions from clients. Every published  Message is "linked" to a Topic.  All Subscribers use a  Topic to "link" to the right Message . How to install Node-Red(NR)  is found here  and the MQ manual here .

For a long time I have checked for a good solution to reach my servers at home. My  thoughts   now have finalized in the VPN solution Zero Tier(ZT) where I reach Ubuntu desktop with "RDP" and Ubuntu server with "ssh". The ZT solution also works great with the Home Assistant(HA) browser access and the HA Mobile App. Until now I have used remote.it but ZT will manage all of my network resources as if they were on the same LAN . The Ubuntu desktop installation is running a Linux KVM with HA and an Ubuntu server Lite as  guests .  Setup here .