XenonStack Recommends

Kubernetes

Introduction to Helm - Package Manager for Kubernetes

Gursimran Singh | 01 November 2023

Introduction to Helm - Package Manager for Kubernetes

Discover the Potential of Kubernetes, IaC and Helm 

Kubernetes is one of the best platforms to deploy and manage containerized applications. But deploying such containerized applications to it can be challenging. You have to write a detailed YAML file to deploy resources like pods, deployments, and services on it that's where it comes into the play.

Helm - the Ultimate Deployment Tool

  1. Enables organizations to swiftly deploy resources to Kubernetes.
  2. Facilitates the deployment of application packages known as charts.

It is also an official its project in the Cloud Native Computing Foundation (CNCF) under the category of incubating projects.

What is Infrastructure as Code ? 

Infrastructure as Code (IaC) manages infrastructures like Networks, VMs, and load balancers in a descriptive model, using the same versioning as the DevOps team uses for source code. The same source code applies the same binary, and its model generates the same environment whenever it is applied.

It is a process of provisioning and maintaining the environment's configuration through YAML code instead of manually creating required servers and storage systems. Once the Code and its parameters are written in YAML-defined configuration files, the system admins and developers need to run scripts, automatically building the cloud infrastructure.

Such automatic IT setups enable people to create the desired infrastructure and test their software quickly. It allows system admins and developers to generate any infrastructure component of their needs, including databases, virtual machines, databases, load balancers, networks, etc.

Completely Managed Kubernetes operations, including monitoring, deployment and optimized usage of its in complex environments. Explore our Services, Managed as a Service

What is Helm?

In general terms, it is a package manager for k8s (Kubernetes). It is the K8s equivalent of yum or apt, which helps deploy the applications on k8s clusters. It charts allow developers and operators to easily package, configure, and deploy applications and services onto K8s clusters. It's a packaged application containing all the versioned and pre-configured application resources deployed as a single unit. Every programming language and OS has its package manager for the installation and maintenance of the software. It also provides the same basic features set as many package managers like Debian, yum, and apt.

In DevOps, among all the challenges, management & deployment of applications on the K8s cluster has proved to be the most complex one for the team. But, due to the runaway success of k8s, there is an evolving ecosystem of tools concentrated on addressing the complexities of app deployment over k8s. Most of these tools exist as open-source projects managed by the developer community. Helm is one such open-source project that has been successfully simplifying the lives of k8s users.

  1. It packages are charts consisting of a few YAML configuration files and templates rendered into the K8s cluster as its manifest files.
  2. Helm Charts helps to install, define and upgrade its application. It will be beneficial to deploy complex applications.
  3. It Charts allow you to version the manifest files too. This helps to install any specific chart versions.
  4. A single chart might be used to deploy something simple or complex, like an entire web application stack with databases, HTTP servers, caches, etc.

Helm Benefits

  1. Its packages can be used using a single CLI command.  
  2. It offers the ability to customize application configurations during deployment. 
  3. It plays a crucial role in streamlining CI/CD pipelines.
  4. It maintains a database of all the versions of your releases automatically. 
  5. It enhances productivity. It lets software developers do what they are best at writing code. With it, deployment of the test environment becomes effortless. 
  6. It reduces the complexity of creating various development, testing, and production environments.
  7. It simplifies its learning curve. Thus, Developers do not require expertise in Kubernetes to start developing and deploying container applications.
Container Design Patterns for Kubernetes are essential for optimizing the efficiency and effectiveness of your application deployments. These patterns provide a set of proven techniques and best practices that can be applied when designing and deploying containers on a Kubernetes cluster.

Kubernetes Deployments with Helm

It makes deployments so easy in it, all you need to add its charts on your Kubernetes cluster. All the charts are stored in its repository; you can search the required application chart on it registry and add them to your cluster with ease. For example, if you want to deploy a WordPress app on your Kubernetes, you have to create Yaml manifest files for deployment and service for both app and database, which can be quite complicated. Still, by using it you can deploy WordPress in a few minutes on your Kube cluster. Also if you want to deploy 50 microservices on it using manifest files it consumes a whole lot of time and also there is an exorbitant probability of errors. Still, in case of it, you have to remember the name of required charts, and you can deploy these as quick as Flash. 

Using Helm for Microservices Deployments 

These are like a "push button" for the deployment and deletion of applications. its chart gives the ability to work with microservices to those who have less experience with containers and microservices. They can quickly deploy the charts and get familiar with its environments. Imagine a microservice deployment approach with and without it. 

Deploy Microservices without Helm

Teams have to depend on Kubernetes YAML manifest files to configure it deployment. These manifest files define everything needed for deploying containers. Everything that each Pod requires to be configured to how the k8s cluster performs load balancing has to be specified in those YAML files. Thus, to deploy a new k8s workload, you need to create a manifest file for that deployment. To do it manually means writing multiple manifest files – one for every k8s object you create.

Deploy Microservices with Helm

Rather than writing every manifest YAML for each application deployment manually, you can easily create a it for that & let it deploy the application to the k8s cluster for you. Its charts contain templates for multiple k8s resources that unite to form an application. It can be customized to deploy on different clusters or environments. Its charts can easily separate env or deployment-specific configurations into a different file. These values can be designated when the its chart is deployed over the cluster.

For example, you can utilize the same charts to deploy an application in different env like development, staging, or production. All can be handled via a single chart with customized config as needed. Click here to know about Microservices Architecture and Design Patterns

It has evolved with time & with every new upgrade. It has ensured that application management on k8s must be simpler. With the latest release of it 3, the benefits have excelled the expectations of the DevOps community. It has been happily included in the must-have tools for deploying applications to k8s.

Installing Helm: A Step-by-Step Process

The process of installing Helm is effortless, you can install it using the binaries, or you can use package managers.

Step 1 - Installation on macOS via homebrew

Start by installing Helm through homebrew on your macOS device.

Step 2 - Installing Helm on Windows using Chocolatey

Another option for installing Helm on Windows is by using the Chocolatey package manager. With just a simple command, "choco install Kubernetes-helm," you can easily install Helm and get started with deploying applications on your Windows machine.

Step 3 - Installing Helm with the Installer Script

It now comes with an installer script, you can fetch this script to your system, and it automatically installs the latest version of Helm in your system. $ curl -fsSL -o get_helm.sh https://raw.githubusercontent.com / helm / helm / master / scripts / get-helm-3 $ chmod 700 get_helm.sh $ ./get_helm.sh

Step 4 - Installing Helm from a Binary Release

Download the required version from "https://github.com/helm/helm/releases" 2. Unpack it using tar -zxvf helm-v3.0.0-linux-amd 64.tar.gz (for linux) 3. Move to helm binary to desired location (mv linux-amd64 / helm /usr / local / bin / helm ) After the installation of Helm in your system you can use the Command "helm version" to check the version of the Helm and also it verifies that Helm is successfully installed in your system.

What is a Helm Chart?

The applications packages in it are called charts; they consist of YAML files and templates that are used for it Deployments.

Structure of Helm Chart:

The structure of a Helm chart is designed to simplify the deployment process and ensure consistency across different applications. It consists of several key components that work together to define and configure the chart's functionality.

|-- Chart.yaml
|-- charts
|-- templates
| |-- NOTES.txt
| |-- _helpers.tpl
| |-- deployment.yaml
| |-- ingress.yaml
| `-- service.yaml
`-- values.yaml

Chart.yaml

This file serves as the blueprint for the chart, providing essential metadata such as the chart's name, version, and keywords. It acts as the guiding force behind the chart's deployment.

README.md

The README file acts as a user-friendly guide, providing detailed information and instructions on how to effectively utilize the chart. It ensures that users can easily navigate and leverage the chart's functionalities without any confusion.

LICENSE

This file contains a plain text license that outlines the terms and conditions for using the chart. It ensures that users adhere to the specified guidelines while utilizing the chart's capabilities.

templates

This directory houses the templates files that form the backbone of the chart. When these templates are combined with the corresponding values, they seamlessly generate the valid manifest files required for successful deployment.

requirements.yaml

This file encompasses a comprehensive list of all the chart's dependencies. It ensures that all necessary components are properly integrated and functioning harmoniously.

values.yaml

This file encompasses the default configuration values for the chart. It acts as a foundational reference point, providing a starting point for users to customize and tailor the chart according to their specific needs.

configmap.yaml

This file holds the essential database configurations required for the chart's functionality. It ensures that the chart seamlessly integrates and interacts with the designated database.

secrets.yaml

This file serves as a secure vault, storing all the necessary database passwords. It guarantees that sensitive information remains protected, allowing for a secure and reliable deployment. These charts can be easily installed from a local directory or a .tar.gz file. Additionally, the repository serves as a convenient platform for users to effortlessly install charts in their Kubernetes environment.

Helm Repository: The Ultimate Collection of Charts

It is a server that acts as an arsenal for its charts. We can use any HTTP server that can serve YAML files and tar files as a it. A Helm repo contains an index.yaml file that has the list of all the packages. On the other hand, at the user side or the client-side command is used to manage the repositories.

Helm Commands:

To install tiller
helm init

To create a chart
helm create <chart name>

To List the repositories
helm repo list

To search a chart
helm search <chart name>

To install a chart
helm install <chart name> <flag>

To inspect a chart
helm inspect <chart> <flag>

Installing Application

Installing apps using it is quite easy; you can install very complex applications in just a few minutes. First of all, you have to add a repo in your system using Helm, and you can install any deployments available in that repo into your Kube cluster. For example, To install Jenkins using it we use Bitnami repository: 

To install Bitnami repository, we'll use the command
helm repo add bitnami https://charts.bitnami.com/bitnami 

To install Jenkins chart with a given name
helm install --name jenk bitnami/Jenkins

To check deployment
kubectl get deploy This command shows you all the
deployments running in your system, and you'll also
see Jenkins deployment there.

Frequently Asked Questions

What is Helm used for?

Helm is a powerful tool used for simplifying the deployment and management of applications on Kubernetes clusters. It provides a convenient way to package, share, and deploy applications using its charts. These charts act as reusable templates that contain YAML files and configuration settings, making it easier to deploy complex applications with just a few simple commands.

With Helm, you can easily search for and install pre-configured charts from its repository, eliminating the need to manually create and manage Kubernetes YAML manifest files. This not only saves time but also reduces the chances of errors that can occur when manually configuring deployments.

How does Helm work?

It enables developers/users/DevOps team to install applications onto the its cluster. Helm also calls itself .

What is Helm's alternative?

AnsibleTerraformKustomize, RancherKubernetes, andDocker are some famous alternatives to it.

Who developed Helm?

DeisLabs developed it, a firm dedicated to helping the its ecosystem. It was later acquired by Microsoft. 

What is Helm vs Docker?

Helm and Docker are popular tools for containerization and application deployment. Helm simplifies application deployment on Kubernetes clusters using charts, while Docker provides the platform and tools for building and distributing containers. Combining both tools streamlines the deployment process and allows for a more efficient application deployment.

kubernetes-services
Advisory Services and deployment strategies for progressive delivery and scable infrastructure to minimise operational tasks of the DevSecOps pipeline ensuring security and compliance. Kubernetes Consulting Services

Helm - The Future of Container Orchestration

Helm provides an effective and efficient way to install and deploy applications. It simplifies deployment on Kubernetes, reducing complexity and allowing for quick app definition and deployment. While it has limitations, such as requiring logic to write templates and some security issues, it is continuously growing and improving with the support of a passionate community. The latest version, Helm3, introduces new features and addresses security concerns, making it an ideal match for Kubernetes.

What's Next? 

Read about Infrastructure as Code (IaC) using Terraform
Also, read Kubecost – Cost Analysis with Kubernetes Monitoring