There seems to be a new trend: every time I get a new job, the first activity I engage in is benchmarking different SDS solutions. My career at Flant is no exception. I joined the development team for the Deckhouse Kubernetes platform when it decided to focus on running virtual machines in Kubernetes. But first, we had to find an easy-to-use, reliable block-type storage that we could offer to the platform’s customers.

Hence I decided to benchmark several Open Source solutions to see how they behave under various conditions. The focal point was the DRBD performance in different configurations and how they compared to Ceph.

However, the market for software-defined storage is constantly growing and evolving. Ambitious new projects are emerging, including the recently released Mayastor and my fellow collaborator’s pet project Vitastor. The results were pretty exciting and surprising.

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When you own two data centers, thousands of physical servers, virtual machines and hosting for hundreds of thousands sites, Kubernetes can actually simplify the management of all these things. As practice has shown, by using Kubernetes, you can declaratively describe and manage not only applications, but also the infrastructure itself. I work for the largest Czech hosting provider WEDOS Internet a.s and today I’ll show you two of my projects — Kubernetes-in-Kubernetes and Kubefarm.

With their help you can deploy a fully working Kubernetes cluster inside another Kubernetes using Helm in just a couple of commands. How and why?

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After 5 years of using Linux, I decided to upgrade to a new MacBook with an M1 chip. Due to the inability to install a full-fledged Linux on it, I’m having fun with OSX. And I have to admit I’m starting to like it.

Tags are set to be as static as it possible and have the same numbering for every display, just like Awesome WM do. This is why you can see so much jq-magic in my skhd config 😃
Some hardware keys are rebinded using Karabiner.

As main browser I use Firefox with TreeStyleTab and Dustman extensions. The last one is closing tabs automatically if I didn’t get on them in 20 minutes. I do believe that tabs are a temporary entity and if I don’t like to close them, why not to run a garbage collector for them?

Terminal configuration and colors moved from my previous laptop.

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First, let’s define what split-brain is. Each replica can be either connected or disconnected towards to the other. If the replica spontaneously goes to StandAlone. It means that it refuses to accept the state and don’t want to synchronize with the other. This is a classic split-brain situation.

Solving the split-brain for two replicas is done in the same way as for multiple replicas.

First, let’s decide which replica we want to synchronize with. To do this, look into

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Over the past few years of tight work with LINSTOR and DRBD9, I have accumulated a some amount of problems and solutions for them. I decided to collect all of them into single article. Not sure that you will face exactly the same problems, but now you could at least understand the mechanics of managing and troubleshooting the DRBD9-devices.

There is not much information on this matter on the Internet. Hope you’ll find it useful in case if you use or plan to use LINSTOR.

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Andrei Kvapil joins the adventure to discuss Kubernetes with Jeffrey Groman.

Andrei breaks down how he and his company needed to set up Kubernetes to manage their blade server setup and how they wound up running Kubernetes in Kubernetes to gain the characteristics they needed. Panel

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Learn more about LINBIT’s SDS solution, its native integration with OpenNebula, and the many benefits it provides to companies using both technologies together. Our guest speakers for this event will be Yusuf Yildiz (Solutions Architect at LINBIT) and Andrei Kvapil (Cloud Architect / DevOps Engineer at WEDOS Internet). For more details, visit: https://opennebula.io/webinars/

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