Master Helm: One‑Click Kubernetes Deployments and Management Guide

Introduction

In Kubernetes, deploying many micro‑service applications one by one with kubectl apply is painful. Helm ( https://helm.sh ) provides a package manager that simplifies deployment.

Helm Features

Simplified deployment : single command installs and manages applications.

Highly configurable : Charts allow easy customization.

Version control : manage multiple versions and rollbacks.

Templating : YAML templates generate Kubernetes objects.

Application library : share and reuse Charts.

Plugin system : extend Helm functionality.

Helm is essentially a Kubernetes package manager.

Helm Workflow (v3)

Helm v3 removes Tiller and interacts directly with the API server via kubeconfig.

Developer creates and edits a Chart.

Package and publish the Chart to a repository.

When an administrator runs helm install, dependencies are downloaded.

Helm deploys the resources to Kubernetes.

Key Concepts

Concept

Description

Chart

A Helm package containing images, dependencies, and resource definitions.

Repository

Storage location for Helm Charts.

Release

An instance of a Chart running in a cluster.

Value

Parameters used to configure Kubernetes objects.

Template

Go‑template files that render Kubernetes manifests.

Namespace

Logical partition for isolating resources.

Using Helm

Install Helm : download binary or use a package manager.

Create a Chart : helm create wordpress Directory contains Chart.yaml, values.yaml, and templates/.

Configure the Chart by editing Chart.yaml and values.yaml.

apiVersion: v2
name: nginx-helm
version: 1.0.0

Package the Chart : helm package wordpress/ Publish the Chart :

helm repo add myrepo https://example.com/charts
helm push wordpress-0.1.0.tgz myrepo

Install a Release : helm install mywordpress myrepo/wordpress Creates a Release named mywordpress with WordPress and MySQL.

Manage Releases : list, upgrade, rollback, uninstall.

helm ls
helm upgrade mywordpress myrepo/wordpress --set image.tag=5.7.3-php8.0-fpm-alpine
helm rollback mywordpress 1
helm uninstall mywordpress

Installation Order

Helm installs resources in the following order: Namespace, NetworkPolicy, ResourceQuota, LimitRange, PodSecurityPolicy, PodDisruptionBudget, ServiceAccount, Secret, SecretList, ConfigMap, StorageClass, PersistentVolume, PersistentVolumeClaim, CustomResourceDefinition, ClusterRole, ClusterRoleList, ClusterRoleBinding, ClusterRoleBindingList, Role, RoleList, RoleBinding, RoleBindingList, Service, DaemonSet, Pod, ReplicationController, ReplicaSet, Deployment, HorizontalPodAutoscaler, StatefulSet, Job, CronJob, Ingress, APIService.

Command Summary

Run helm --help for a full list of commands and environment variables.