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Helm Fundamentals

Deploying, upgrading, and rolling back applications in Kubernetes

Topic: System Administration
Brent Laster

Helm is like a package manager and lifecycle manager for Kubernetes; think of it as something like yum or apt. Helm exists because managing all of the different manifests for the various objects that make up a Kubernetes application can be challenging, particularly if you want to reuse them for different use cases. Helm simplifies this by bundling related manifests into a “chart” and managing installed charts in clusters as “releases.”

Join expert Brent Laster to discover what Helm is and how it works. You’ll get hands-on as you learn how to use, create, and modify functions for use with Helm and how to create and modify a Helm chart. You’ll leave ready to get started with Helm, simplifying the process of managing groups of manifests and managing the lifecycle for applications in Kubernetes, including installing, upgrading, rolling back, deleting, and more—ensuring repeatability, reusability, and reliability in a way you couldn’t do without it.

What you'll learn-and how you can apply it

By the end of this live online course, you’ll understand:

  • What Helm is and what functions it serves
  • How Helm can be used to install, upgrade, configure, and rollback software
  • What makes up a Helm chart
  • How values are substituted into charts
  • How functions can be used to modify values and augment charts

And you’ll be able to:

  • Use Helm to install, upgrade, configure, and roll back an application
  • Create a Helm chart
  • Create functions through Helm to add additional functionality to charts

This training course is for you because...

  • You’re a Kubernetes user who needs to be able to deploy Helm charts.
  • You create applications for Kubernetes and need to be able to package and deploy them easily.
  • You’re a Kubernetes user who needs to be able to make modifications to existing Helm charts.

Prerequisites

Recommended follow-up:

About your instructor

  • Brent Laster is a global trainer, author, and speaker on open source technologies as well as an R&D director at a top technology company. He’s been involved in the software industry for more than 25 years, holding various technical and management positions. Brent has always tried to make time to learn and develop both technical and leadership skills and share them with others. He believes that regardless of the topic or technology, there’s no substitute for the excitement and sense of potential that come from providing others with the knowledge they need to accomplish their goals.

Schedule

The timeframes are only estimates and may vary according to how the class is progressing

What is Helm? (45 minutes)

  • Presentation: Helm basic concepts, intents, and functionality; why Helm exists; what it’s used for; the components of Helm; what a Helm chart is; how values are specified for Helm; how basic Helm deployments are done; the differences between Helm 2 and Helm 3
  • Hands-on exercise: Create a simple Helm chart from existing Kubernetes manifests and deploy it into a Kubernetes cluster

Break (5 minutes)

Customizing Helm deployments (40 minutes)

  • Presentation: How value substitution works with Helm through values.yaml files; how Helm values can be passed in via the command line to override existing values at different levels; the format of the value substitutions; best practices for picking which values to substitute; using the Helm “template” command to render results without applying them
  • Hands-on exercise: Create values.yaml files and run with Helm; pass in values from the command line to override sets of existing values

Using Helm functions and pipelines (35 minutes)

  • Presentation: Helm template functions and pipelines and how they work; how to use functions and pipelines in charts and deployments; how Helm upgrades work
  • Hands-on exercise: Utilize existing Helm functions and pipelines in an upgrade deployment

Break (5 minutes)

Creating Helm functions (35 minutes)

  • Presentation: The Sprig templating language; example—creating a Helm function and using it in an install
  • Hands-on exercise: Create a simple Helm function, then leverage it in a Helm install

Wrap-up and Q&A (15 minutes)

  • Presentation: How to find and locate Helm charts; how Helm compares to Kustomize (a newer Kubernetes orchestration solution); additional topics of interest