Helm

Helm is a tool for managing Kubernetes applications.

For Helm, there are a few important concepts:

• A Chart is a collection of files that describe a related set of Kubernetes resources that define an instance of a Kubernetes application.
• A Repo is a chart registry. Repositories can be added to Helm.
• A Config contains configuration information merged into a packaged chart to create a releasable object.
• A Release is a running instance of a chart using a specific configuration.

Commands

A short list of common Helm commands

Repos

Add, update, and search repos for installable charts

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

A valid chart repository must have an index file. The index file contains information about each chart in the chart repository. The following command will generate an index file based on a given local directory that contains packaged charts.

helm repo index

Install and Remove Charts

helm install provide-a-name-here bitnami/apache
helm uninstall provide-a-name-here bitnami/apache

Create New Chart Template

Helm create name-of-chart-dir

Issues

1. If attempting to install an application via Helm results in Error: Kubernetes cluster unreachable, make sure the KUBECONFIG environment variable is set properly:

export KUBECONFIG=/etc/rancher/k3s/k3s.yaml

2. An application gets stuck in a CrashLoopBackOff status and the Kubernetes logs show exec user process caused "exec format error"

The lab Kubernetes cluster is using Raspberry Pi 4s, which are 64-bit ARM architecture. The above is a common error when the container application is built for an x86 architecture. To resolve this issue, use a container targeted for 64-bit ARM.