Deploying Applications with Helm Charts

Tutorial 3 of 5

1. Introduction

Brief Explanation of the Tutorial's Goal

In this tutorial, we will explore Helm Charts and how they can be used to deploy applications on a Kubernetes cluster. Helm Charts offer a simple, powerful way to manage and deploy applications, and we will walk through the process from start to finish.

What the User Will Learn

By the end of this tutorial, you will be able to create, configure, and use Helm Charts to deploy your applications on a Kubernetes cluster.

Prerequisites

Before starting, you should have a basic understanding of Kubernetes, including how to create and manage clusters. Familiarity with YAML files will be helpful. You will also need to have Helm and Kubernetes installed on your system.

2. Step-by-Step Guide

Helm and Helm Charts

Helm is a package manager for Kubernetes. It simplifies the process of managing and deploying applications on Kubernetes. Helm Charts are packages of pre-configured Kubernetes resources.

Creation of Helm Charts

First, you need to create a Helm Chart for your application. Run the following command to create a new Helm Chart:

helm create mychart

This will create a new directory 'mychart' with all the necessary files to start configuring your application.

Configuring Helm Charts

Inside the 'mychart' directory, you will find a file named 'values.yaml'. This file is used to provide default configuration values for your chart.

replicaCount: 1
image:
  repository: nginx
  tag: stable
  pullPolicy: IfNotPresent

3. Code Examples

Deploying Helm Charts

To deploy your Helm Chart, use the following command:

helm install myapp ./mychart

This command deploys your application on the Kubernetes cluster with the configuration specified in your chart.

Checking Deployment Status

To check the status of your deployment, use this command:

helm status myapp

4. Summary

In this tutorial, you've learned how to create, configure, and deploy applications using Helm Charts. You've also learned how to check the status of your deployments.

5. Practice Exercises

  1. Create a Helm Chart for a simple application and deploy it on your local Kubernetes cluster. This exercise will test your understanding of creating and configuring Helm Charts.

  2. Modify your Helm Chart to use a different image or configuration. This exercise will test your ability to modify and update Helm Charts.

  3. Create a Helm Chart that deploys a multi-service application. This more advanced exercise will challenge your understanding of more complex Helm Charts.

Solutions and Explanations

  1. You should be able to create a Helm Chart and deploy it using the 'helm create' and 'helm install' commands respectively.
  2. Modifying your Helm Chart requires editing the 'values.yaml' file. Make your changes, save the file, then update your deployment using the 'helm upgrade' command.
  3. A multi-service application requires multiple services defined in your Helm Chart. Each service should have its own section in the 'values.yaml' file.

Tips for Further Practice

To get more practice with Helm Charts, try deploying a variety of applications with different configurations. Explore how Helm can manage dependencies between charts, and how you can use it to roll back deployments.