Today I was cleaning out an old moving-box, and found a very old small project of mine 😉 It’s a set of game / quiz buttons, which record who did press first. There were only two buttons connected, but the circuit was suitable for 4 of them (two were cut off). There’s no circuit diagrams or software available, it’s just a bunch of images and movies to show the old stuff. It’s a simple setup, you can almost guess the…
A quest I took at 2 November, making my own docker log plugin. Suitable to share with everyone. At the office, we are mixing docker-only hosts, with on-premise kubernetes clusters. For example our databases do run better / more stable on plain docker hosts, with no kubernetes intervention. That’s mainly due to the sub-optimal distributed storage in our on-premise cluster. But… we do want to send all of the logs from both kubernetes and docker hosts to a central logging…
Intro Now why would I want to create an alert light? 😉 The use case I had in mind was work related; in our team we do monitor a bunch of kubernetes/docker server clusters, a set of software build tools/services, and an oauth secured open-api-gateway. To keep an eye on this during office hours, we have some big dashboard monitors in the room, showing nice graphs and red/green alert boxes. However, sometimes when you are working on something, it takes…
Github Project: https://github.com/atkaper/k8s-check-certificate-chains Ingress/nginx (running in Kubernetes / K8S) does not like silly certificates, therefore I created two scripts to find wrong ones. The script get-all-k8s-certificates.sh retrieves all certificates from kubernetes, and the check-certificate-chains.sh script verifies the chain’s are complete and in proper ordering. Added md5 hash check on crt and key file to verify the two belong to each other. The check-certificate-chains.sh just reports on WRONG certificates. Run with “-v” option to also show OK’s. Thijs.
At the office, we have quite a bunch of Java developers. However, because we are quickly growing (way, way, way too quick in my opinion), there was an intake exam created, as part of sourcing in new Java coders from external companies. One of the questions on the intake was an interesting one, so we took it upon ourselves (the existing oldies) to try creating not the most beautiful, but the FASTEST way to get the job done 😉 See…
Github Project: https://github.com/atkaper/simple-tcp-vpn-over-ssh-socks Poor-man’s VPN for TCP traffic over SSH dynamic socks tunnel, uses Linux/iptables Taken some TCP tunneling code from Christophe Devine, and turned it into a transparent socks proxy. This serves as a lightweight / poor-man’s VPN connection, to combine firewalled networks into one. Requirements; use linux on your end, and you need to be able to connect to an SSH server on the network you want to reach. And the local and remote network IP-ranges should NOT…
Github Project: https://github.com/atkaper/k8s-network-test-daemonset Description An on-premise K8S (kubernetes) cluster needs a proper working virtual network to connect all masters and nodes to each other. In our situation, the host machines (vmware redhat), are not all 100% the same, and can not easily be wiped clean on new K8S and OS upgrades. Therefor we sometimes experienced issues in which the nodes or masters could not always reach each other. We did use the flannel network, which often caused weird issues. We…
Github Projects: https://github.com/atkaper/pebble-simpleweek-nl and https://github.com/atkaper/pebble-simplicity-nl Pebble is a smartwatch, once created by a no longer existing company as a kickstarter project in 2012. See wikipedia for more info; https://en.wikipedia.org/wiki/Pebble_(watch) I do own a couple of these watches, and did create my own “watch face” for it. I still use the simpleweek-nl one, which displays the time, date, day, and week number. The “strange” number in the top left corner is indicating the year divided by 13 (4 week periods), as…