Helm Notes — Table of Contents

1. Introduction to Helm

  • What is Helm?
  • Why use Helm in Kubernetes?
  • Helm vs kubectl
  • Helm key concepts (Chart, Release, Repository, Values, Templates)

2. Helm Architecture

  • Helm v3 workflow (client-side)
  • Interaction with Kubernetes API
  • Where Helm stores release data in the cluster

3. Helm as a Package Manager (Pre-Built Charts)

  • Definition: Installing & managing existing charts (apps/controllers)
  • Adding a repo (helm repo add)
  • Searching charts (helm search repo)
  • Installing from a repo (helm install release-name repo/chart)
  • Upgrading from a repo (helm upgrade release-name repo/chart)
  • Uninstalling releases
  • Example: Installing ingress-nginx from Bitnami repo
  • Example: Upgrading cert-manager from a repo

4. Creating & Managing Your Own Application Chart

  • Creating a chart (helm create)
  • Chart directory structure explained
  • Editing templates & values
  • Linting your chart (helm lint ./chart-dir)
  • Installing your own chart locally
  • Upgrading your own chart locally
  • Packaging your chart (helm package)
  • Hosting your chart in a repo
  • Installing from your own repo
  • Example: MyApp chart with upgrade

5. Chart Values & Customization

  • Purpose of values.yaml

  • Overriding values during install

  • --set key=value

  • -f my-values.yaml
  • Combining multiple values files
  • Example: Customizing image and replicas

6. Release Management

  • Listing releases (helm list)
  • Viewing release details (helm status)
  • Upgrading (helm upgrade)
  • Rolling back (helm rollback)
  • Uninstalling (helm uninstall)
  • Example: Rollback after a failed upgrade

7. Helm Template Engine

  • Template basics
  • Go templating syntax
  • _helpers.tpl usage
  • Example: Dynamic Deployment YAML

8. Troubleshooting Helm

  • --dry-run and --debug
  • Viewing rendered manifests before install (helm template)
  • Common errors and solutions

9. Helm in CKA Exam Context

  • Common scenarios in the exam
  • Fast installation tricks
  • Repo management under time pressure

10. Helm Quick Reference

  • Most used commands
  • Common flags

  • Flow diagrams for both use cases:

  • Installing from repo

  • Creating & installing your own chart