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I started this blog in order to share and learn new fun stuff on system adminstration and full stack web development. You can reach me via e-mail.

Create a k0s Kubernetes Cluster with Ansible

January 03, 2021

Last November, the new Kubernetes distro k0s was released by Mirantis. The distribution has already collected 3k likes on Github in this short time. k0s promises to simplify the deployment of Kubernetes clusters massively. It combines all the required K8s components into a single binary. I put together a Ansible playbook that you can use to create a k0s Cluster in automated fashion.

Monitoring Traefik 2 with Icinga

May 06, 2020

I monitor personal web services with good old Icinga2. Last year I wrote a small Python script that runs on the Icinga2 hosts that queries the Traefik API to automate the generation of Icinga2 rules. For me this was a nice and useful exercise to learn how to use REST APIs together with Python for system administration. In this article I would like to share the lessons learned.

Talk on visual regression testing at c't webdev 2020

February 06, 2020

In the spring of last year, I wrote two blog posts on visual regression testing on the “Know-how from the RRZK Cologne” blog (where I’m employed). There I described how the Puppeteer Headless Browser API together with the Image comparison library ResembleJS can be used to roll your own Visual Regression Testing tool. I was therefore very excited when I was invited to speak at the c’t webdev 2020 conference on the topic. This is how my first presentation at a technical conference came about…

Upgrading to Traefik 2 with Docker

December 13, 2019

This fall containous the company behind Traefik released version 2.0. This is a major release including cool stuff like reusable middlewares, a new fun web dashboard and advanced stuff for production deployments like canary deployments. This changes come with a trade off. The new version has lots of breaking changes because of that I had to update my deployment and understand the new paradigms introduced. In this post I want to help share my findings and show a path to upgrade from 1.7 to 2.1.

Sending emails via SMTP on Ubuntu or Debian Servers

November 25, 2019

I used to sift trough my shell history and bookmarks every time set up sending email on a new Debian or Ubuntu server. This should help…