Certified Kubernetes Application Developer (CKAD) Study Guide, 2nd Edition

Chapter 12. Helm

Helm is a templating engine and package manager for a set of Kubernetes manifests. At runtime, it replaces placeholders in YAML template files with actual, end-user-defined values. The artifact produced by the Helm executable is a so-called chart file bundling the manifests that comprise the API resources of an application. You can upload the chart file to a chart repository so that other teams can be use it to deploy the bundled manifests. The Helm ecosystem offers a wide range of reusable charts for common use cases searchable on Artifact Hub (for example, for running Grafana or PostgreSQL).

Due to the wealth of functionality available to Helm, we’ll discuss only the basics. The exam does not expect you be a Helm expert; rather, it wants you to be familiar with the workflow of installing existing packages with Helm. Building and publishing your own charts is outside the scope of the exam. For more detailed information on Helm, see the user documentation. The version of Helm used to describe the functionality here is 3.13.0.

Coverage of Curriculum Objectives

This chapter addresses the following curriculum objective:

• Use the Helm package manager to deploy existing packages

Managing an Existing Chart

As a developer, you want to reuse existing functionality instead of putting in the work to define and configure it yourself. For example, you may want to install the open source monitoring service Prometheus on your cluster.

Prometheus requires the installation ...