Docker & Kubernetes · Module 13

Helm – The Package Manager for Kubernetes

Package manifests as charts, install and upgrade releases with values, roll back by revision, and manage chart dependencies.

Practice interactively →

What you will learn

• Compare deploying with kubectl and with Helm
• Explain charts, releases, repositories and Helm 2 vs Helm 3
• Describe the chart layout and create, lint and render a chart
• Write templates with built-in objects, pipelines and helpers; upgrade and roll back releases
• Declare dependencies and subcharts

Lessons

1. Why Helm — the kubectl Way and the Helm Way

   Helm bundles many manifests into one parameterised chart and installs it as a release with history, so upgrades and rollbacks are easy.

2. Concepts and Architecture — Helm 2 and Helm 3

   A chart is the package, a release is one installation, a repository is where charts are shared; Helm 3 removed Tiller and stores releases in Secrets per namespace.

3. Chart Structure

   A chart is a folder with Chart.yaml, values.yaml and templates/; helm create scaffolds one, helm lint checks it, helm template renders it.

4. Template Syntax and Values

   Helm templates are Go templates — actions in {{ }}, built-in objects such as .Values and .Release, pipelines, if/range, include helpers; values are overridden with -f or --set.

5. Dependencies, Subcharts and Repositories

   Declare dependencies in Chart.yaml and download them into charts/ with helm dependency update; values only flow from the parent chart down to subcharts.