Helm Cheatsheet¶

Quick reference for essential Helm commands and concepts.

Installation¶

# Install Helm (Linux)
curl https://raw.githubusercontent.com/helm/helm/main/scripts/get-helm-3 | bash

# Verify installation
helm version

Repositories¶

# Add a repository
helm repo add <name> <url>
helm repo add stable https://charts.helm.sh/stable
helm repo add bitnami https://charts.bitnami.com/bitnami

# List repositories
helm repo list

# Update repository index
helm repo update

# Remove a repository
helm repo remove <name>

# Search for charts
helm search repo <keyword>
helm search repo nginx
helm search hub <keyword>        # Search Artifact Hub

Installing Charts¶

# Install a chart
helm install <release-name> <chart>
helm install my-nginx bitnami/nginx

# Install in a specific namespace
helm install my-nginx bitnami/nginx --namespace web --create-namespace

# Install with custom values
helm install my-nginx bitnami/nginx --values values.yaml
helm install my-nginx bitnami/nginx --set replicaCount=3
helm install my-nginx bitnami/nginx --set image.tag=1.25,replicaCount=2

# Install a specific chart version
helm install my-nginx bitnami/nginx --version 15.0.0

# Dry run (preview without installing)
helm install my-nginx bitnami/nginx --dry-run
helm install my-nginx bitnami/nginx --dry-run --debug

# Generate manifests without installing
helm template my-nginx bitnami/nginx
helm template my-nginx bitnami/nginx --values values.yaml

Managing Releases¶

# List releases
helm list
helm list -A                     # All namespaces
helm list --namespace web

# Get release status
helm status <release-name>

# Get release history
helm history <release-name>

# Get release values
helm get values <release-name>
helm get values <release-name> --all   # Include default values

# Get rendered manifests for a release
helm get manifest <release-name>

Upgrading Releases¶

# Upgrade a release
helm upgrade <release-name> <chart>
helm upgrade my-nginx bitnami/nginx

# Upgrade with new values
helm upgrade my-nginx bitnami/nginx --values values.yaml
helm upgrade my-nginx bitnami/nginx --set replicaCount=5

# Install if not exists, upgrade if exists
helm upgrade --install my-nginx bitnami/nginx

# Reuse existing values during upgrade
helm upgrade my-nginx bitnami/nginx --reuse-values

# Rollback on failure
helm upgrade my-nginx bitnami/nginx --atomic
helm upgrade my-nginx bitnami/nginx --atomic --timeout 5m

Rolling Back¶

# Rollback to previous revision
helm rollback <release-name>

# Rollback to specific revision
helm rollback <release-name> <revision>
helm rollback my-nginx 2

# Dry run rollback
helm rollback my-nginx 2 --dry-run

Uninstalling Releases¶

# Uninstall a release
helm uninstall <release-name>
helm uninstall my-nginx

# Uninstall but keep history
helm uninstall my-nginx --keep-history

Chart Information¶

# Show chart information
helm show chart bitnami/nginx
helm show values bitnami/nginx      # Default values
helm show readme bitnami/nginx
helm show all bitnami/nginx

# Download chart locally
helm pull bitnami/nginx
helm pull bitnami/nginx --untar     # Extract after download
helm pull bitnami/nginx --version 15.0.0

Creating Charts¶

# Create a new chart scaffold
helm create <chart-name>
helm create my-app

# Validate chart syntax
helm lint <chart-directory>
helm lint ./my-app

# Package chart into a .tgz archive
helm package <chart-directory>
helm package ./my-app

Chart Structure¶

my-app/
├── Chart.yaml          # Chart metadata
├── values.yaml         # Default values
├── charts/             # Chart dependencies
├── templates/          # Kubernetes manifest templates
│   ├── deployment.yaml
│   ├── service.yaml
│   ├── ingress.yaml
│   ├── _helpers.tpl    # Template helpers / partials
│   ├── NOTES.txt       # Post-install notes
│   └── tests/
│       └── test-connection.yaml
└── .helmignore         # Files to ignore when packaging

Chart.yaml Fields¶

apiVersion: v2
name: my-app
description: A Helm chart for my application
type: application        # application | library
version: 0.1.0           # Chart version (SemVer)
appVersion: "1.0.0"      # App version (informational)
dependencies:
  - name: postgresql
    version: "12.x.x"
    repository: https://charts.bitnami.com/bitnami
    condition: postgresql.enabled

Templating Basics¶

# Reference values
{{ .Values.replicaCount }}
{{ .Values.image.repository }}

# Release metadata
{{ .Release.Name }}
{{ .Release.Namespace }}
{{ .Release.IsInstall }}
{{ .Release.IsUpgrade }}

# Chart metadata
{{ .Chart.Name }}
{{ .Chart.Version }}
{{ .Chart.AppVersion }}

# Conditionals
{{- if .Values.ingress.enabled }}
# ... ingress resource
{{- end }}

# Loops
{{- range .Values.env }}
- name: {{ .name }}
  value: {{ .value }}
{{- end }}

# Default values
{{ .Values.replicas | default 1 }}

# Quote strings
{{ .Values.image.tag | quote }}

# Include helper template
{{ include "my-app.fullname" . }}

Managing Dependencies¶

# Update chart dependencies
helm dependency update <chart-directory>
helm dependency update ./my-app

# List dependencies
helm dependency list ./my-app

# Build dependencies (from Chart.lock)
helm dependency build ./my-app

Testing¶

# Run chart tests
helm test <release-name>

# Run tests with logs
helm test my-nginx --logs

Plugins¶

# List installed plugins
helm plugin list

# Install a plugin
helm plugin install <url>
helm plugin install https://github.com/databus23/helm-diff

# Popular plugins
# helm-diff    - Show diff between releases
# helm-secrets - Manage encrypted secrets
# helm-push    - Push charts to OCI registries

OCI Registry Support¶

# Login to OCI registry
helm registry login <registry>

# Push chart to OCI registry
helm push my-app-0.1.0.tgz oci://registry.example.com/charts

# Install from OCI registry
helm install my-app oci://registry.example.com/charts/my-app --version 0.1.0

# Pull from OCI registry
helm pull oci://registry.example.com/charts/my-app --version 0.1.0

Useful Flags¶

Flag	Description
`--namespace` / `-n`	Target namespace
`--create-namespace`	Create namespace if it doesn't exist
`--values` / `-f`	Specify values file
`--set`	Override individual values
`--dry-run`	Simulate without applying
`--debug`	Enable verbose output
`--atomic`	Roll back on failure
`--timeout`	Time to wait for operations (default 5m)
`--wait`	Wait for pods to be ready
`--version`	Specify chart version
`--output` / `-o`	Output format (table, json, yaml)