Graphing Raspberry Pi performance with sar

As part of monitoring the general health of my Raspberry Pi boxes, i like keeping a historical image of how the load was at a given time. I have real time monitoring in place, which will alert me via Pushover if something goes haywire1, and my surveillance does it’s own checking and alerts (via the same pushover container) if a sensor fails to report within a given period. I based my graph generating script on the one described here, though the memory calculation in that script is not what i wanted, and this being a memory restricted platform, i also wanted to monitor swap in/out. [Read More]

Playing Around with Go

I’ve previously described my temperature monitoring solution, written in Python, and I’ve also described my various attempts at optimizing this solution, using NodeRED and Apache Camel, but all of these attempts have been focused on the server side, while the client has been mostly left to itself. The client runs on an old Raspberry Pi B+, with a total of 256MB RAM. The RPi also runs a surveillance camera, via the RPi camera module, which requires a memory split of 128 MB. [Read More]

Monitoring temperatures with Apache Camel

Intro I’ve been trying out various technologies for my temperature monitoring project, but all of them have been more or less unstable. The python solution is by far the most robust, but can lose connection to the MQTT broker, and stubbornly refuse to reconnect by itself. The Node-RED solution is, while fast to write, notoriously unstable regarding MQTT connections. Connections sit “idle” showing a connected state, while in fact they are disconnected, and there is no obvious way of reconnecting it - apart from restarting the docker container. [Read More]

Temperature monitoring with Node-RED

I originally wrote my temperature monitoring software using Python, and while my Python solution works (almost) flawlessly, I recently became aware of Node-RED, a project initiated at IBM, meant as a controller for the Internet of things. When i read about Node-RED i wanted to try it out, so i decided to port my temperature/surveillance monitoring solution from python to Node-RED, and while i’m not much of a JavaScript fan, it actually worked out rather well. [Read More]

Monitoring temperatures with a Raspberry Pi.

I recently got into a discussion about dogs, kennels and temeratures. I have a German Shepherd, and he has a nice insulated dog house in his kennel, and the discussion was along the lines, how much heat does it take to warm up the doghouse, if it gets hotter than the outside at all. Now, a normal person would have solved this by putting a wireless meat thermometer in the doghouse, made a few readings of it with/without the dog, and compare it to the outside temperature. [Read More]

Sending notifications with MQTT and

I’ve improved a bit on my setup, described in this previous article. I started using MQTT, namely the Mosquitto broker for sending data to/from my machines, instead of the old point-to-point setup i was using. MQTT provides publish/subscribe, with messages up to 256MB each. It also features QoS, ranging from 0 - which basically just means the message was sent on the network, to 2, where you have guaranteed delivery of messages to the broker. [Read More]