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 .

Updated 2025-08-25 ! What is the purpose of a Home Assistant(HA)  according to Wikipedia ? Home Assistant is free and open-source software used for home automation. It serves as an integration platform and smart home hub, allowing users to control smart home devices. The software emphasizes local control and privacy and is designed to be independent of any specific Internet of Things (IoT) ecosystem.  Even for me, as someone running Apple HomeKit and Homebridge, it is a fantastic piece of software that bridges almost everything and enables highly intelligent integrations.  Since it is widely used, there is a wealth of information available. However, I couldn't find a clear "bullet list" on how to get started. This post will primarily contain links to other sources rather than writing extensive explanations myself.

  I really like the products on AliExpress and Alibaba, but in most cases the documentation is very simple and to short. So when I bought a combined tracker and a burglar alarm, to our boat, I really tried to get the best. One important thing was that, if possible, getting a lifetime app support. The purchase went well and 14 days later it arrived in Sweden.

It's almost become a sport to revive old Macs..... 😉 This short post will address some obstacles found during install of a new OS. The Mac Mini:s WiFi controller wasn't found ! The MacBook Air didn't manage to do a USB boot with Ubuntu !

Updated 2025-06-28 ! Are You searching for a solution where You want to create graphs and gauges from SignalK(SK) data ? Use NodeRed(NR), installed as a SK plugin , with the standard dashboard and it's easy to create info as seen in the picture. And this is without a database as InfluxDB and tools like Grafana. You use the WebSocket interface , or SK subscribe nodes, to subscribe to changes in data from the SK server. 

Updated 2025-06-23 ! I have got some questions installing, just,  Signal K (SK) so will do a summary with links. Signal K is the hub to receive data, from different devices in different data formats, and send it on to different equipment, or databases, in different formats. Most common for standard marine equipment are the old NMEA 0183 and the newer NMEA 2000 protocol which is also handled.  Besides the SK "hub" function developers  have  created  plugins  for different purposes. This is due to that  SK is open-source ! Sharing is caring ! In this post you can check the devices I'm using connected to the SK server and also my setup.

We’ve been using Mobile Broadband for several years and have always been keen to measure the speed from our Internet Service Provider (ISP). I’ve posted several variants , mostly Node-RED(NR) flows and programs that often use Python. I’m now slowly converting to Home Assistant(HA), and was glad there was an integration,   Speedtest , to do the job.  But I couldn’t get it to work since HA didn’t like that the test took more than 10 seconds,  Then I tried a Speedtest NR node, but it didn’t install because it needed Python dependencies...... (NR was installed as a HA "Add-on")