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Ivan Velichko

Building labs.iximiuz.com - a place to help you learn Containers and Kubernetes the fun way πŸš€

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Ivan on the Server Side

Hello πŸ‘‹ It's this time of the month again! My traditional roundup of all things Linux, Containers, Kubernetes, and Server Side, delivered straight into your inbox πŸ“¬ What I was working on October was very productive for me - I shipped no major iximiuz Labs features (it's always hard to resist the temptation!) and instead dedicated all my available time to content work. The main focus was on Container Images. It's the subject of the first module of my "panoramic" Docker course, and it is almost...

Hey there, I’ve just finished putting together everything I know about Node.js container images and figured you might find the write-up useful. If you’re working with Node.js in Docker, chances are you’ve been hit by the dilemma of which base image to use. Do you go for the default node:latest, the slimmer node:22-slim, or something super minimal like a distroless image? What about Bitnami’s alternative β€” how does it stack up? Before you jump headfirst into your next build, you might want to...

Hello πŸ‘‹ Ivan's here with a slightly delayed September roundup of all things Linux, Containers, Kubernetes, and Server Side πŸ§™ What I was working on This month, I worked on an assorted set of topics. Skill Paths First off, the skill paths! I finally finished the underlying machinery, and now iximiuz Labs supports a new type of content - short roadmaps that you can use to develop or improve a specific skill: how to debug distroless containers, how to copy images from one repository to another,...

Hello friends! Ivan's here with another monthly roundup of all things Linux, Containers, Kubernetes, and Server Side πŸ§™ The issue's main topic is iximiuz Labs' largest-ever upgrade: Fresher and more streamlined look of the frontend UI πŸ’™ A new 5.10 Linux kernel built with nftables support (finally, we can try out kube-proxy's nftables mode). New default playground user - laborant (yep, rootless containers learning for). New playgrounds: Ubuntu 24.04, Debian Trixie, Fedora, and Incus (yay! more...

Hello friends! Ivan's here with a slightly delayed July roundup of all things Linux, Containers, Kubernetes, and Server Side πŸ§™ What I was working on This month, I got nerd-sniped by cgroups. It all started when I ran into a pretty significant difference in how Docker and Kubernetes handle the OOM events. When you limit the memory usage of a multi-process Docker container, the OOM killer often terminates only one of the processes if the container runs out of memory. If this process is not the...

Hey there πŸ‘‹ I spent a few weeks deep diving into cgroup v2, and I'm happy to share my findings with you! Everyone knows that Docker and Kubernetes use cgroups to limit the resources of containers and Pods. But did you know that it's very easy to run an arbitrary Linux process in a cgroup using much more basic tools? The only kernel's interface for cgroups is the virtual filesystem called cgroupfs typically mounted at /sys/fs/cgroup. Creating folders there and writing to files in them is...

Hello friends! Ivan's here with the June roundup of all things Linux, Containers, Kubernetes, and Server-Side craft πŸ§™ What I was working on The first two lessons (and a few challenges) of my "Alternative Introduction to Dagger" course have not sparked much interest among my students, so I had to put this work on pause. With a heavy heart, though, because I do like Dagger, and I was enjoying working on the content about it. But no interest means fewer iximiuz Labs Premium subscribers, and I...

Hello friends! It's time for my traditional monthly roundup of all things Linux, Containers, Kubernetes, and Server-Side craft πŸ§™ Before we get started, I want you to know that this newsletter's previous issue (dispatched mid-May) was delivered to only about 1/5th of my usual email audience due to an unfortunate DNS misconfiguration. The good news is that you can still find it and all previous issues on newsletter.iximiuz.com. Also, if you reply to this email, it'd help to restore the domain's...

Hello friends! Ivan's here - with another well overdue roundup of all things Linux, Containers, Kubernetes, and Server-Side craft πŸ§™ This time, I have a great excuse - in April, we became parents of a lovely little boy. Expectedly, he immediately made us overly busy for a few weeks, but no complaints! I wouldn't trade this business for anything else in my life ❀️ Now, to more technical news. What I was working on My main focus remains on iximiuz Labs πŸš€ Content authoring redesign In March &...

Hello friends! Ivan's here - with a well overdue February roundup of all things Linux, Containers, Kubernetes, and Server-Side craft πŸ§™ What I was working on A lot of stuff on the dev side - not so much on the content side. But things are soon to reverse 🀞 Announcing labCTL - the long-awaited iximiuz Labs CLI A dozen people have asked me over the past year-ish if there'll be access to the playgrounds from the local terminal and not only from the browser. And while I myself wanted this feature...