Static pods are pods which are not managed by the Kubernetes control plane. Normally, the kubelet running on each node in a cluster watches the kube-api for instructions to launch or delete pods. However, in the case of static pods, the kubelet can manage pods by watching for manifests added to a directory or a […]
Exploring Static Pods Read More »
This is going to be a short article, showing a couple of ways to output terraform sensitive data. If you don’t know what that is, basically, you can declare a variable as sensitive and terraform will prevent that data from appearing in CLI and log output. But beware – the data is still saved in
Output a Terraform Sensitive Value Read More »
Why External Secrets Operator Whenever we talk about secrets in Kubernetes, we typically mean sensitive data that should be shared with applications. These are things like API keys, database credentials, certificates, tokens, etc. Kubernetes has a native Secret Object that can expose secrets to pods, however, there are some drawbacks with the built-in approach: To
Getting Started with External Secrets Operator Read More »
If you search for information about setting CPU requests and limits for containers, you might end up becoming even more confused from all the conflicting advice on the topic. This article is my attempt to understand how CPU requests and limits work. In Kubernetes, CPU behaves differently from memory. CPU resources are compressible, meaning you
Understanding CPU Requests and Limits Read More »
You may have heard of StatefulSets in Kubernetes. But if you’ve never had the chance to work with them, it might be hard to understand what purpose they serve. In this article we will review when to use StatefulSets and provide a quick walkthrough of how to create one. Why Stateful Sets StatefulSet is the
Demystifying Stateful Sets Read More »
After upgrading our EKS Kubernetes clusters from 1.23 to 1.24, some pods went into crashloopbackoff, with the following curious error: I know some of you are thinking – Geez, everyone knows you are not supposed to use privileged ports as container ports ! But that’s not the point here. We run a cluster with shared
Trouble Binding Ports After Switching to Containerd? Read More »
If you are running an AWS EKS cluster, there is a good chance you use the amazon-vpc-cni-k8s plugin for managing pod networking using Elastic Network Interfaces on AWS. There is also a very good chance that you use vpc-cni with the default configuration, which is usually fine in most cases. However, I ran into a
Tuning AWS vpc-cni for Short-Lived Worker Nodes Read More »
Helmfile is a wrapper around the helm command that helps you manage multiple helm charts with a single command. It encourages DRY and allows you to pass different values based on environments that you define. If you’ve never heard of helmfile, I recommend having a look at this excellent open-source tool. I’d like to share
Mapping Chart Versions to Cluster Versions using Helmfile Read More »
Besides being the subject of hilarious debate about its pronunciation, kubectl is of course the Kubernetes command line interface. Everyone working with Kubernetes has some kind of go-to list of favorite commands. Even the official Kubernetes site offers a kubectl cheat sheet. These are some of my favorite commands. Disclaimer: even though many of these
A Kubectl Cheat Sheet Read More »
I’m a big fan of ArgoCD – and I’m a big fan of Helmfile. In this article I will describe how to create an ArgoCD Configuration Management Plugin (CMP) for deploying helm charts using helmfile. If you use ArgoCD for deploying to Kubernetes, you’ll know that ArgoCD has built-in support for helm, jsonnet, kustomize, and
Using ArgoCD with Helmfile Read More »
