Lesson 01 — Introduction to Helm

Lesson 01 · Slide 1

Introduction to Helm

The package manager for Kubernetes — from raw manifests to repeatable, versioned deployments in minutes.

Learning Objectives

Understand what Helm solves and why it exists
Learn the Helm 3 architecture (no Tiller, client-only)
Master core concepts: charts, releases, repositories, values
Discover community charts on Artifact Hub
Run your first helm install and compare it to raw kubectl apply

Lesson 01 · Slide 2

The Problem Helm Solves

Deploying to Kubernetes typically means writing and maintaining many YAML manifests — Deployments, Services, ConfigMaps, Secrets, Ingresses, and more. As applications grow, this approach breaks down.

Without Helm

Dozens of YAML files per app
Copy-paste to change environments
No versioning of deployments
No rollback mechanism
Hard to share configurations

With Helm

One chart packages all manifests
Values files parameterize environments
Every install is a versioned release
One-command rollback
Share via repositories

Notes: Think of Helm as "apt" or "brew" for Kubernetes — it packages, versions, and manages applications as a single unit.

Lesson 01 · Slide 3

Helm 3 Architecture

Helm 3 removed the server-side component (Tiller) that existed in Helm 2. It is now a client-only tool that talks directly to the Kubernetes API.

Helm 2 (Legacy)

Required Tiller pod in-cluster
Tiller had broad RBAC permissions
Security concerns (cluster-admin by default)
Release state stored in ConfigMaps

Helm 3 (Current)

No Tiller — pure client-side
Uses your kubeconfig credentials
Respects existing RBAC policies
Release state stored as Secrets

Notes: Release secrets are stored in the same namespace as the release itself. You can see them with kubectl get secrets -l owner=helm.

Lesson 01 · Slide 4

Key Concepts

Helm revolves around four core abstractions that work together to manage Kubernetes applications.

Concept	What It Is	Analogy
Chart	A package of templated Kubernetes manifests	A `.deb` or `.rpm` package
Release	A running instance of a chart in a cluster	An installed package on a machine
Repository	A collection of charts available for download	An apt/yum repository
Values	Configuration parameters that customize a chart	A config file for the package

Chart Structure (Preview)

mychart/
  Chart.yaml          # Metadata (name, version, description)
  values.yaml         # Default configuration values
  templates/          # Kubernetes manifest templates
    deployment.yaml
    service.yaml
    ingress.yaml

Lesson 01 · Slide 5

Artifact Hub & Repositories

Artifact Hub is the central place to discover, install, and publish Kubernetes packages including Helm charts.

Working with Repositories

# Add the official Bitnami repository
helm repo add bitnami https://charts.bitnami.com/bitnami

# Update local repo index
helm repo update

# Search for charts
helm search repo nginx

# Search Artifact Hub directly
helm search hub wordpress

Popular Chart Repositories

Bitnami — largest collection of curated, production-ready charts
Prometheus Community — monitoring stack (Prometheus, Grafana, Alertmanager)
Ingress NGINX — NGINX ingress controller
Jetstack — cert-manager for TLS certificates

Lesson 01 · Slide 6

helm install Basics

Installing a chart creates a release — a named, versioned instance of the application in your cluster.

# Install nginx with release name "my-nginx"
helm install my-nginx bitnami/nginx

# Install with custom values
helm install my-nginx bitnami/nginx --set service.type=ClusterIP

# Install with a values file
helm install my-nginx bitnami/nginx -f my-values.yaml

# Check release status
helm status my-nginx

# List all releases
helm list

Values Override Order

Values are merged in this priority (highest wins):

--set flags on the command line
-f values.yaml file(s)
Chart's default values.yaml

Lesson 01 · Slide 7

kubectl apply vs Helm

A side-by-side comparison of managing the same application with raw manifests versus Helm.

Operation	Raw kubectl	Helm
Deploy	`kubectl apply -f ./manifests/`	`helm install myapp ./mychart`
Update	Edit YAML, `kubectl apply` again	`helm upgrade myapp ./mychart`
Rollback	Find old YAML, apply manually	`helm rollback myapp 1`
Delete	`kubectl delete -f ./manifests/`	`helm uninstall myapp`
Version history	None (unless GitOps)	`helm history myapp`
Multi-env config	Kustomize overlays or copy files	`-f staging.yaml` / `-f prod.yaml`

Notes: Helm does not replace kubectl — it generates manifests and applies them via the Kubernetes API. You can always inspect what Helm will send with helm template.

Lesson 01 · Slide 8

Lab & Homework

Lab Exercises

Install Helm and verify the installation
Add a repository, search for charts, and inspect chart details
Install a chart with custom values and explore the release

Homework Tasks

Compare deploying an app with raw manifests vs Helm
Explore Artifact Hub and document 5 charts
Perform an upgrade and rollback cycle

Reference

Official Helm docs: helm.sh/docs

Artifact Hub: artifacthub.io