Pravar Agrawal Technology & Travel

An Intro to Kubernetes Descheduler

If I were to mention “control plane” in Kubernetes, then automatically four components would come in our minds: kube-apiserver, etcd, kube-scheduler and kube-controller. And out of these four as we know, kube-scheduler is the one which is responsible for assigning our workload pods to the nodes in a K8s cluster. But, often we see our worker node resources are not utilized properly. Since, the kube-scheduler doesn’t take any responsibility in re-scheudling the pods from highly utilized nodes to under-utilized nodes, we are sometimes left with our cluster resources not being used fully.

2021 and 2022

As we all are ready to say goodbye to year 2021 and welcome 2022, let me pen down few of my personal updates here. They may sound boring and maybe a little beneficial for many like me who are always looking to better themselves from yesterday. This post is more about my goals in 2021 , how much of it was I able to achieve and what plans I have for 2022, more like a boring retrospective of my life in 2021.

Amazing Bash Script Options

Linux has become the de-facto operating system these days especially for servers. Most of us have been using Linux operating systems almost every day and it has become a need to understand this OS from it’s very basic to it’s core. Though there are many tutorials, posts available online which could help us in learning more about Linux, in this post I’ll be discussing few not so popular and some very common syntax being used for bash scripting.

How K8s Scheduler Works

Kubernetes is the mostly wide used Container ecosystem in present times. With it’s roots dating back to Google’s Borg, Kubernetes is itself a collection of multiple microservices. The Kubernetes architecture comprises of around 5 major components in it’s master plane. And kube-apiserver being the heart of whole cluster, there is one component called kube-scheduler which is actually responsible for managing the workloads throughout the cluster. Though there is not much available in detail regarding kube-scheduler’s working in Kubernetes docs, with this blog post I’ll try to bring some less explored and mysterious ways kube-scheduler works.

2021 So Far

As we all know year 2020 will go down in the history due to a tiny virus called SARS Covid-19. With almost the whole world coming to a stand-still early last year, it’s been difficult since then coming back to normal. The first, Second waves of Covid infections have kept all of us on back-foot. For us, IT folks working-from-home has been the new-normal and that’s pretty much the story in past one year.

Quay vs Others

Container Registry is the salt of container ecosystem, serves best when fully utilised. The term became more familiar from the early days of Docker Hub but now, there are many players in this segment too. Quay, ECR, ICR(IBM cloud container registry), Google Cloud Registry, Azure Container Registry etc. In this post, I’ll be particularly talking about Quay which is maintained by RedHat and how it’s different from others. A container registry is a single place for you and your team to manage container images be it with Docker, Podman etc.

Understanding Argo CD

Continuous Delivery is an eminent pillar of DevOps culture and is very popular in present times. There are many tools available today which are slowly paving it’s path towards being a must to have in our kitty. One such tool which I’m closely following for a while now is Argo CD. Argo project has been there for quite some time now and I’ve enjoyed working on both Argo workflows and Argo CD.

Podcasts I Listen To

Wikipedia defines a podcast as “an episodic series of spoken word digital audio files that a user can download to a personal device for easy listening”. In other words, a digital audio version of your favourite shows which you can listen to anytime by either simply downloading those or streaming them online. In this post, I’ll be discussing about my favourite podcasts which I regularly listen to. The very first podcast which I listened to was of the show Off the Hook, which is actually a radio show broadcasted on WBAI radio station.

Go - Closures & Variadic functions

“The best programming language is the one which works best for you and the one which you are most comfortable with” - Kelsey Hightower I really like this quote from Kelsey Hightower as it really solves the most confusing question of all time, which programming language is best? Even though I’ve been working with Go for a while, I still come along it’s new features especially whenever I run into a new problem.

Power Up With Helm3

If you are already familiar with the Kubernetes world, usage of Helm is indispensable. It’s an immensely powerful utility when it comes to managing deployments, upgrades to Kubernetes resources. Earlier, there were few concerns especially in terms of security about using Helm. But with the introduction of Helm v3, those issues have been fixed with addition of new features . Before we jump into Helm v3, let’s understand a little about it’s previous version.