Helm Quick Reference

Helm is package + release management for Kubernetes.

Repos and Search

# Add and update repos
helm repo add bitnami https://charts.bitnami.com/bitnami
helm repo update

# List repos and charts
helm repo list
helm search repo nginx

# Chart info
helm show chart bitnami/nginx
helm show values bitnami/nginx
helm show all bitnami/nginx

Install / Upgrade / Uninstall

# Install (creates a release)
helm install <release> bitnami/nginx -n <ns> --create-namespace

# Upgrade (or install if missing)
helm upgrade --install <release> bitnami/nginx -n <ns>

# Pin a chart version
helm install <release> bitnami/nginx --version 15.10.0 -n <ns>

# Uninstall
helm uninstall <release> -n <ns>

Values and Overrides

# Layer values files (later wins)
helm upgrade --install <release> ./chart -n <ns> \
  -f values.yaml \
  -f values.prod.yaml

# One-off overrides
helm upgrade --install <release> ./chart -n <ns> \
  --set image.tag=1.2.3 \
  --set-string env.LOG_LEVEL=debug

# See computed values for an installed release
helm get values <release> -n <ns>
helm get values <release> -n <ns> --all

Render and Debug

# Render templates locally
helm template <release> ./chart -n <ns>

# Validate chart structure
helm lint ./chart

# Dry-run an install/upgrade (talks to cluster if --dry-run=server)
helm upgrade --install <release> ./chart -n <ns> --dry-run --debug

# Show the manifest Helm applied
helm get manifest <release> -n <ns>

# Release status
helm status <release> -n <ns>

History and Rollback

# See revisions
helm history <release> -n <ns>

# Roll back to a prior revision
helm rollback <release> <revision> -n <ns>

Tests and Hooks

# Run chart tests (if defined)
helm test <release> -n <ns>

Notes:

Hooks are Kubernetes Jobs/Pods annotated with helm.sh/hook (pre-install, post-upgrade, etc.).
A rollback re-applies Kubernetes resources; it does not automatically undo side effects like database migrations.

Dependencies

# Update / vendor dependencies
helm dependency update ./chart
helm dependency build ./chart

OCI Registries

# Login and pull charts from OCI
helm registry login <registry>
helm pull oci://<registry>/<org>/<chart> --version 1.2.3

# Install directly from OCI
helm install <release> oci://<registry>/<org>/<chart> --version 1.2.3 -n <ns>

Common Gotchas

Namespaces: Helm releases are namespace-scoped; always pass -n <ns> consistently.
Values typing: --set guesses types; use --set-string when you need literal strings.
Secrets in values: avoid committing credentials in values*.yaml; prefer External Secrets / SOPS / Sealed Secrets.
Diffs: the helm-diff plugin is the usual workflow (helm plugin install https://github.com/databus23/helm-diff).