Helm Basics for Application Packaging

Helm packages Kubernetes resources so applications can be installed, configured, upgraded, and rolled back more consistently.

Kubernetes Field Notes · Application Delivery · Estimated reading time: 22 minutes

What this lesson covers

Helm is a package manager for Kubernetes. It helps install, upgrade, configure, and uninstall applications using charts.

• What Helm is
• What a chart is
• What values are
• How Helm releases work
• How to install a chart
• How to upgrade and uninstall a release
• How to inspect generated manifests

The short version

Chart:
  A packaged Kubernetes application.

Values:
  Configuration inputs for the chart.

Release:
  An installed instance of a chart in a cluster.

Before you start

This lab assumes Helm is installed. If it is not, install it using your normal package manager, then verify:

helm version
kubectl config current-context
kubectl get nodes
kubectl create namespace helm-lab

Step 1: Add a chart repository

helm repo add bitnami https://charts.bitnami.com/bitnami
helm repo update

Step 2: Search for a chart

helm search repo bitnami/nginx

Step 3: Inspect chart default values

helm show values bitnami/nginx

Values control how the chart renders Kubernetes manifests.

Step 4: Install a chart

helm install nginx-helm-lab bitnami/nginx -n helm-lab

helm list -n helm-lab
kubectl get all -n helm-lab

Step 5: Inspect the release

helm status nginx-helm-lab -n helm-lab
helm get values nginx-helm-lab -n helm-lab
helm get manifest nginx-helm-lab -n helm-lab

helm get manifest is important because it shows the Kubernetes YAML Helm sent to the cluster.

Step 6: Create a custom values file

Create a file named:

nginx-values-lab.yaml

replicaCount: 2
service:
  type: ClusterIP
resources:
  requests:
    cpu: 100m
    memory: 128Mi
  limits:
    cpu: 500m
    memory: 256Mi

Step 7: Upgrade the release

helm upgrade nginx-helm-lab bitnami/nginx -n helm-lab -f nginx-values-lab.yaml

helm status nginx-helm-lab -n helm-lab
kubectl get pods -n helm-lab

Step 8: View release history

helm history nginx-helm-lab -n helm-lab

Step 9: Roll back a release

helm rollback nginx-helm-lab 1 -n helm-lab
helm history nginx-helm-lab -n helm-lab

Step 10: Render templates locally

helm template nginx-helm-lab bitnami/nginx -n helm-lab -f nginx-values-lab.yaml

This lets you preview the generated Kubernetes YAML before applying it.

Step 11: Uninstall the release

helm uninstall nginx-helm-lab -n helm-lab
helm list -n helm-lab
kubectl get all -n helm-lab

Common Helm commands

helm repo list
helm repo update
helm search repo <name>
helm show values <chart>
helm install <release> <chart> -n <namespace>
helm upgrade <release> <chart> -n <namespace> -f values.yaml
helm list -n <namespace>
helm status <release> -n <namespace>
helm history <release> -n <namespace>
helm rollback <release> <revision> -n <namespace>
helm uninstall <release> -n <namespace>

Common mistakes

• Installing charts without reviewing values.
• Assuming Helm values are security-reviewed by default.
• Not pinning chart versions in real environments.
• Forgetting that Helm creates normal Kubernetes resources.
• Using Helm without understanding the rendered manifests.

Step 12: Clean up

kubectl delete namespace helm-lab

Check your understanding

1. What is a Helm chart?
2. What is a Helm release?
3. What do values control?
4. What command installs a chart?
5. What command upgrades a release?
6. What command shows rendered Kubernetes YAML from an installed release?
7. What command previews rendered manifests without installing?
8. Why should chart values be reviewed?
9. What command rolls back a release?
10. Does Helm replace Kubernetes knowledge?