Kubernetes Lesson 3 | Using Helm Charts

1. Introducing the Helm Chart

  1. Helm is the ultimate Kubernetes package manager

  2. Helm Charts are the Kubernetes packages. \

  3. Helm is to Kubernetes what Yum or Apt is to linux.\

  4. Artifacthub is to Helm Charts what Dockerhub is to Docker Images

2. How to use Helm to deploy applications

  1. Using existing Helm Charts.

    • Production grade Helm Charts created by the developers of the applications
    • Production grade Helm Charts created by VMware (Bitnami Charts)

  2. Making your own Helm Charts

    • packaging your Manifests into Helm Charts

3. Why do we want to use Helm Charts

  1. Reusability:

    • Helm charts allow developers to package and share their applications as a self-contained unit.
    • This makes it easy to reuse charts across different projects, which can save time and effort.

  2. Versioning:

    • Helm charts provide a versioning system that helps you manage changes to your application over time.
    • This means that you can easily roll back to a previous version if something goes wrong or if you need to test an earlier version.

  3. Dependency management:

    • Helm charts support dependency management, so you can easily manage complex application deployments that require multiple services or components.

  4. Configuration management:

    • With Helm, you can easily manage configuration settings for your application.
    • This means that you can store different configuration files for different environments (such as Development, UAT, and Production) and easily switch between them.

  5. Scalability:

    • Helm charts are designed to be scalable, which means that you can easily deploy your application to multiple clusters or nodes.

  6. Standardization:

    • Helm charts provide a standardized way to deploy applications on Kubernetes.

4. Installing Helm into Linux

Run the following commands

# Download Helm
curl -L https://get.helm.sh/helm-v3.11.1-linux-amd64.tar.gz -o helm.tar.gz

# Extract Archive
tar -xvzf helm.tar.gz

# Move to servers bin folder
sudo mv linux-amd64/helm /usr/local/bin/

# Verify installation
helm version

4.1 K3S Server requirements

nano ~/.bashrc

Put this ontop of the file

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

You need to reboot

# Reboot the server
sudo reboot

5. A quick tour of Artefacthub

https://artifacthub.io/

  1. We will search for postgre
  2. we will choose : PostgreSQL packaged by Bitnami
  3. The buttons on the RHS
    • Install ( Add repository | Install chart)
    • Templates (All the manifests used for this deployment)
    • Default values (The values-postgresql.yaml file)

Grafana Helm Chart using the Bitnami repository