Helm Package Management in Kubernetes

Quiz

Helm is a package manager for Kubernetes that simplifies the deployment, configuration, and management of applications. In this guide, we'll use Helm to define, install, and upgrade complex Kubernetes applications using Helm charts. This tool is particularly useful in production environments where consistency, automation, and ease of upgrades are essential.

Why Use Helm?

Helm charts encapsulate application dependencies and configurations, reducing manual effort. Deploying a complex application like WordPress becomes straightforward with just a few commands.

Helm maintains version history, allowing us to easily roll back to previous configurations if something goes wrong. This provides the ability to revert to a stable state after an unsuccessful upgrade.

Helm ensures uniform deployments across multiple environments. Whether it's staging, testing, or production, we can be confident that the deployments are consistent.

Helm allows us to override values without modifying the core configurations. It means we can customize our deployments for different environments without changing the underlying code.

Installing Helm

To install Helm on Ubuntu, well start by running the following command −

$ curl -fsSL https://raw.githubusercontent.com/helm/helm/main/scripts/get-helm-3 | bash

During installation, Helm downloads the necessary binaries and verifies the checksum before installing −

Downloading https://get.helm.sh/helm-v3.17.1-linux-amd64.tar.gz
Verifying checksum... Done.  
Preparing to install helm into /usr/local/bin 
helm installed into /usr/local/bin/helm

Once installed, verify the installation by checking the Helm version −

$ helm version

Output

version.BuildInfo{Version:"v3.17.1", 
GitCommit:"980d8ac1939e39138101364400756af2bdee1da5", 
GitTreeState:"clean", GoVersion:"go1.23.5"}

This confirms that Helm has been successfully installed and is ready for use.

Helm Architecture

Helm consists of two main components −

Helm CLI − The command-line tool used to interact with Helm charts.
Helm Charts − Pre-configured application definitions, similar to package managers like apt or yum.

Helm Charts

A Helm chart is a collection of YAML files defining Kubernetes resources and configurations. Helm charts simplify the deployment of complex applications such as MySQL, Prometheus, and more.

Creating a Helm Chart

To create a custom Helm chart, we'll use the following command −

$ helm create mychart

This command generates a directory structure −

$ ls

Output

charts Chart.yaml templates values.yaml

The key components include −

Chart.yaml − Contains metadata about the chart, such as the name, version, and description.
values.yaml − Defines default configuration values that we can override during deployment.
templates/ − Contains Kubernetes manifest templates, which define the actual resources to be created.

Installing a Helm Chart

To deploy an application using a Helm chart, we'll use the following command −

$ helm install myapp ./mychart

If the chart is located in the current directory, the path should be prefixed with ./ to avoid errors.

Once installed, Helm confirms a successful deployment −

NAME: myapp 
LAST DEPLOYED: Wed Feb 26 16:09:44 2025
NAMESPACE: default
STATUS: deployed
REVISION: 1

To verify the deployed Helm release, we will use the following command −

$ helm list

Output

NAME NAMESPACE REVISION UPDATED STATUS CHART APP VERSION
myapp default 1 2025-02-26 16:09:44.191518589 +0300 
EAT deployed mychart-0.1.0 1.16.0

Accessing the Application

After deployment, we can retrieve the application's pod name and container port with −

$ export POD_NAME=$(kubectl get pods --namespace default -l
"app.kubernetes.io/name=mychart,app.kubernetes.io/instance=myapp" 
-o jsonpath="{.items[0].metadata.name}")
$ export CONTAINER_PORT=$(kubectl get pod --namespace default $POD_NAME 
-o jsonpath="{.spec.containers[0].ports[0].containerPort}")

Then, we forward the application's port to make it accessible locally −

$ kubectl --namespace default port-forward $POD_NAME 8080:$CONTAINER_PORT

Once port forwarding is active, we can visit http://127.0.0.1:8080 in a browser. If everything is working correctly, we should see the following welcome page −

This confirms that the application is running correctly and is accessible through port forwarding. In this case, we deployed an Nginx-based application, and the default welcome page indicates that Nginx has been successfully installed.

Using Helm with Real-World Applications

Deploying MySQL with Helm

We can deploy a MySQL database using Helm. First, we add the Bitnami repository −

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

Output

"bitnami" has been added to your repositories

Update the repository −

$ helm repo update

Output

Hang tight while we grab the latest from your chart repositories...
...Successfully got an update from the "bitnami" chart repository
Update Complete. Happy Helming!

Deploy MySQL −

$ helm install mymysql bitnami/mysql

Output

NAME: mymysql
LAST DEPLOYED: Wed Feb 26 19:36:12 2025
NAMESPACE: default
STATUS: deployed
REVISION: 1
TEST SUITE: None
NOTES:
CHART NAME: mysql
CHART VERSION: 12.3.0
APP VERSION: 8.4.4

Verify the deployment −

$ kubectl get pods

Output

NAME                             READY   STATUS      RESTARTS   AGE
myapp-mychart-7d49757dc6-xqrqt   1/1     Running     0          3h48m
mymysql-0                        0/1     Pending     0          93m 
test-pod                         0/1     Completed   0          31h

Upgrading a Helm Release

If changes need to be applied, we can upgrade the deployment using −

$ helm upgrade myapp mychart

Output

Release "myapp" has been upgraded. Happy Helming!
NAME: myapp
LAST DEPLOYED: Wed Feb 26 16:21:55 2025
NAMESPACE: default
STATUS: deployed
REVISION: 2

Uninstalling a Helm Release

To remove a Helm deployment, use −

$ helm uninstall myapp

Output

release "myapp" uninstalled

Helm Rollbacks

If an upgrade introduces issues, we can roll back to a previous release by using the following command −

$ helm rollback myapp 1

Output

Rollback was a success! Happy Helming!

This reverts the deployment to revision 1. If a faulty update is deployed, rolling back ensures application stability.

Helm Best Practices

Here is a list of some of the best practices while using Helm -

Use version-controlled Helm charts for consistency across deployments.
Use values.yaml to manage configurations without modifying templates.
Regularly update repositories to ensure we are using the latest chart versions.
Test charts in a staging environment before deploying to production.

Conclusion

Helm is an essential tool for managing Kubernetes applications efficiently. It simplifies deployments, enables version control, and provides a consistent way to package applications. By leveraging Helm charts, we can deploy, upgrade, and manage applications with minimal manual effort.

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