Kubernetes

Sidecarless? Why not podless?

How Istio tests its networking proxy without Kubernetes, Docker, or root.

Like most other Kubernetes controllers in, Istio is written in Go and relies on the client-go library. While this provides an excellent low-level building block, usage in higher level code in Istio led to a variety of issues that led us to develop our own higher level, opinionated client for Istio. This post covers the issues we faced and how we incrementally solved them. Background knowledge At a high level, client-go provides a few layers for interactions with the API server:...

Rage bait for YAML templating haters

How and why to easily these fields

Most people using Kubernetes extensive have already defined alias k=kubectl and are using tools like kubectx. As someone really lazy though, I have found/developed a few less common tools to help work with Kubernetes efficiently. kubectl apply from clipboard This relies on zsh, and uses the zle to define a custom command. function zle_apply { LBUFFER=" cat <<EOF | kubectl apply -f - $(xclip -se c -o) EOF" CURSOR=31 } zle -N zle_apply; bindkey "^k" zle_apply This defines a function and binds it to Ctrl+k....

How versioning works in Kubernetes, especially with CustomResourceDefinitions, is a common source of confusion. The documentation is pretty comprehensive but a bit complicated. This post aims to give a simple description of how versioning works and dispel some misunderstandings. There is only one primary version Consider a CRD with versions alpha and beta. A user can create and view either resource version. Intuitively, they must be distinct things -- they are not....

Kubernetes Operators are powerful tools when used right, pushing complex operations from human operators to code. This sounds great - and is in some cases - but often the tradeoffs operators expose are not taken into account, both by operator developers and users. This article goes over my take on when operators are useful and not, and what makes a good operator. A basic installation operator A common feature amongst almost all operators is the ability to deploy Kubernetes resources....