Helm, often referred to as the “Kubernetes package manager” simplifies the process of managing Kubernetes applications. If you are new to Kubernetes or want to streamline your application deployment, Helm can be a powerful tool in your DevOps toolkit. In this blog post, we will explore What Helm is, its key components, and how to get started with it.
What is Helm?
Helm is an open-source tool that helps you manage Kubernetes applications. It allows you to define, install, and upgrade even the most complex Kubernetes applications. Helm does this by using “charts” which are packages of pre-configured Kubernetes resources.
Key Components of Helm
1. Helm CLI
The command line interface for interacting with Helm.
2. Helm Charts
Pre-configured templates of Kubernetes resources.
3. Helm Repositories
Collections of Helm charts that can be shared and reused.
4. Release
An instance of a chart running in a Kubernetes cluster.
Benefits of using Helm
- Simplified Deployment : Helm simplify the deployment of applications by bundling together all necessary Kubernetes mainfests.
- Version Control : Helm allows for easy version management of your applications, making rollbacks straightforward.
- Sharing and Reusability : Helm charts can be shared and reused across teams and projects, fostering collaboration and consistency.
Getting started with Helm
Here’s a quick guide to get you started with Helm;
1. Install Helm
- Follow the official Helm installation guide for your operating system.
- Verify the installation by running helm version.
2. Add a Helm Repository
- Helm uses repositories to distribute charts. You can add official stable repository with,
helm repo add stable https://charts.helm.sh/stable
3. Search for Helm Charts
- Use the helm search command to find charts in the repository,
helm search repo stable
4. Install a Helm Chart
- To install a chart use the helm install command,
helm install my-release stable/mysql
- Above command installs the MYSQL chart from the stable repository and names the release as my-release.
5. Upgrade and Rollback Releases
- Helm makes it easy to upgrade your applications,
helm upgrade my-release stable/mysql
- If something goes wrong you can rollback to a previous version ,
helm rollback my-release 1
6. Uninstall a Release
- To uninstall release and clean up it’s resources,
helm uninstall my-release
Creating Your Own Helm Chart
Creating your own helm chart allows you to package your custom applications. Here’s a simple example,
1. Create a New Chart
helm create my-chart
2. Customize Your Chart
- Edit the values.yaml file to specify default values for your application.
- Modify the templates in the templates/directory to define the Kubernetes resources.
3. Install Your Chart
helm install my-app ./my-chart
4. Package and Share Your Chart
helm package my-chart
helm repo index .
Conclusion
Helm is a powerful open source tool for managing Kubernetes applications, offering ease of deployment, version control and reuse ability. By understanding it’s core components and following the basic steps to get started, you can leverage Helm to streamline your Kubernetes workflows. Whether you’re deploying existing applications or packaging your ow, Helm provides a structured and efficient approach to Kubernetes application management.
FAQ’s
Can we use Helm with other Kubernetes tools?
Ans : Yes, Helm can be used alongside other Kubernetes tools such as kubectl, kubeadm and various CI/CD tools. Helm charts can be integrated into deployment pipelines to automate application deployment and management.
What are Helm values file?
Ans : Values file (values.yaml) contain the default configuration values for a Helm chart. These values can be overridden by providing your own custom values file or by using the –set flag during installation pr upgrade.
How do we customize a Helm chart?
Ans : We can customize the Helm chart by editing the values.yaml file to provide our desired configuration or by using the –set flag to override specific values. Additionally we can modify the template file in the templates/directory to change the Kubernetes resources.
Where can we find official Helm charts?
Ans : Official Helm charts can be found in the Helm hub, which hosts charts from the Helm community and other trusted sources.