Introduction

Helm, the package manager for Kubernetes, provides a powerful feature to customize deployments using values files. The helm install --values command allows users to override default configuration values defined in Helm charts with custom values from external files. In this article, we'll explore the helm install --values command, its functionality, and provide a step-by-step guide along with a practical example to demonstrate how to customize Helm charts effectively using Helm.

1. Understanding helm install --values Command: The helm install --values command is used to override default configuration values defined in Helm charts with custom values from external files. It enables users to customize deployments based on specific requirements without modifying the original Helm chart files.

2. Customizing Helm Charts: Let's customize a Helm chart named "my-chart" using values from an external YAML file named "custom-values.yaml" using the helm install --values command.

   Example:

    $ helm install my-release my-chart --values custom-values.yaml
   

   Output:

    NAME: my-release
    LAST DEPLOYED: Mon Jan 24 15:04:12 2022
    NAMESPACE: default
    STATUS: deployed
    REVISION: 1
    TEST SUITE: None
    NOTES:
    1. Get the application URL by running:
       echo "http://$(kubectl get svc --namespace default my-release --template '{{ range (index .status.loadBalancer.ingress 0) }}{{.}}{{ end }}')"
   

   • The output confirms the successful deployment of the release "my-release" with customized values from the "custom-values.yaml" file.

   • It provides instructions for accessing the deployed application, including the application URL.

3. Interpreting the Output:

   • The output confirms that the deployment was successful using custom values provided in the "custom-values.yaml" file.

   • It indicates that the release has been deployed with the specified custom values, ensuring the desired configuration for the application.

4. Customization Best Practices:

   • Ensure that the custom values provided in the external file align with the expected structure and format defined in the Helm chart.

   • Use descriptive names and comments in the values file to document the purpose of each customized value for clarity and maintainability.

Conclusion

The helm install --values command is an essential feature of Helm, allowing users to customize deployments effectively with external values files. By understanding how to use this command and interpreting its output, users can tailor Helm charts to specific requirements without modifying the original chart files, enhancing deployment flexibility and efficiency in Kubernetes environments.