A nice open source project from the industry. The new plant of a medium-sized company needed to be equipped with video surveillance and recording. Usually engineers use ready-to-use CCTV1 systems bought in DIY stores, consisting of a network-attached storage and a streaming server. Nowadays, not that cheap Chinese blackboxes, usually tied together with Apps, Cloud and Online functionality without any chance of customization. Better keep away from this especially when information security, valueable corporate assets and the lives of people are at stake. Read more

Congratulations to Telekom with its millions of MagentaCloud1 users. Throughout the year2, they will switch to Nextcloud3 and the online office service Collabora4, based on the free LibreOffice5. This is a real success story for Nextcloud and its years of work in winning over ISPs6. This reduces the arguments of proponents of Microsoft365 solutions who consider Nextcloud, Collabora, or Libreoffice as niche solutions. In recent years, I have personally seen the exact opposite. More and more people are using open-source solutions as a replacement for unpredictable and expensive subscription license models. Read more

The Linux Presentation Day (LPD)1 on 19.11.2022 is intended to promote the free operating system and its applications to anyone interested. All over Germany2 universities, user groups, computer and chaos clubs will open their doors simultaneously and invite people to: Discover the various free operating systems and applications Exchange experiences in a cosy atmosphere Installation session of PCs, notebooks or media centres On this day, I will be present at the Chaostreff Dortmund from 1 p.m. on3 and will give two inspiring LightningTalks on the following topics: Read more

Today, I’m excited to write about a special migration. This time, it’s me who’s switching from proprietary to free software. The challenge is navigation - not by car, bicycle, or foot. It’s about flying in the sky with an airplane. Admittedly, this is a niche with only a few players. Finding an open-source project here is delightful! Unfortunately, there’s no space for a built-in device in the cockpit of my open biplane. The typical mounts with suction cups and goosenecks are out of scope as they’re not secure in wind and weather conditions. Besides, a display would ruin the charm of a historically-inspired biplane with an analogue “clock store”. Read more

Visualisations, live feeds from surveillance cameras or digital display solutions (eSignage) usually run on classic PC hardware. Hidden in industrial cabinets and protected enclosures, a lot of effort is spent when the only thing that matters is often the display of a simple web application. In addition, there are license or cloud subscriptions that companies rarely need. In the upcoming c’t issue 12/2022 starting 21 May, I show in a 4-page practical article1 how small single-board Raspi computers with free Debian and Firefox manage this task better and more economically. Read more

Hard-wired networks are usually provided with numerous security features. With wireless networks, however, admins often remain blind to intrusion attempts, which can be carried out by inexperienced users thanks to affordable gadgets. The remedy is a Wireless Intrusion Detection System (WIDS). Sounds expensive, but it isn’t. A Raspi, a Wi-Fi stick and free open-source software are all you need. In the upcoming c’t edition 19/2021, starting on 28 August, I will show in a “hardcore” article of several pages how to better protect your own wireless network1. Read more

Recently I was looking for a very particular music track. It is a song from the 2017 anime adaptation of “Ghost in the Shell” with Scarlett Johansson. More precisely: the official trailer music1, which was not included in the sound score and therefore cannot be found in any of the mainstream music stores. That’s the downside of a few keeping an entire industry under technological and legal control. The coveted piece of music is the cyberpunk cover version of the 80s song “Enjoy the Silence” by Depeche Mode, reinterpreted by Joel Burleson2 aka Ki:Theory3. Read more

Over the weekend I have increased security and automatized processes - that’s lame! This can be anything or nothing, too vague and unspecific. Well technically correct and with a touch of cynicism: “I translated bash scripts to YAML.” Okay, let’s agree on: I consolidated numerous bash scripts for automatically renewing certificates, reduced complexity, eliminated potential security risks when transferring certificates from outside reverse proxies to inside hosts, and made everything more transparent with both Ansible and Git. Read more

The simple, unspectacular things in life bring you ahead the curve. This bash script, for instance, removes all comments from a configuration file. In order that no empty lines remain instead, these are subsequently removed afterwards. What remains is the essence: what really counts. The usage is straightforward: Just add the desired config file(s) as parameters and you’re done! #!/bin/bash # Beseitigt alle Kommentar- und Leerzeilen aus einer Configfile # Sichert Datei mit Erweiterung .backup und # erwartet Dateiname oder -liste als Parameter for FILE in "$@" do # Erstellt Sicherungskopie(n) cp --backup=numbered $FILE $FILE.backup # Entfernt alle Kommentarzeilen > Arbeitsdatei sed -e 's/#.*$//' $FILE > $FILE.tmp # Entfernt alle Leerzeilen aus Arbeitsdatei sed -i '/^$/d' $FILE.tmp # Ersetzt Ausgangsdatei mit Arbeitsdatei mv $FILE.tmp $FILE done; This simplifies automation and above all the search in page-long comments within a config file. However, be careful! Behind every line theres much of wisdom: Everything after a # sign is mercilessly removed, really everything! Take the following line as example: Read more

The last two days I improved my own architecture and extended everything with a PDF workflow. If you like, you may download my larger blog series from the previous year in one piece as a PDF file and read them offline, a total of 75+ pages of condensed facts: Corona Warning App Home Office Workplaces Macbook Revival Come on, PDFs for old articles? Seriously? Well these are just test-balloons and working examples for my new PDF workflow. With the help of Pandoc, Git, Bash and Xelatex I have been able to achieve a significant improvement. The three linked PDFs are 100% automatically created from the content of this blog without my intervention. In future, this workflow will also be used for audits, documentation or other articles for third parties. Read more