Step-by-Step Guide to Deploying Apps on Minikube Kubernetes

Introduction

Kubernetes has revolutionized container orchestration, making it easier to manage, scale, and deploy applications. If you're new to Kubernetes, Minikube is a great way to get started. In this guide, we will walk through the process of setting up Minikube and deploying a simple application using Kubernetes.

Understanding the Basics

What Are Containers?

Containers are lightweight, portable, and self-sufficient environments that include everything needed to run an application. Technologies like Docker have made containers popular.

What Are Pods?

In Kubernetes, a Pod is the smallest deployable unit. A Pod can contain one or more containers that share networking and storage resources.

What Is a Deployment?

A Deployment is a higher-level Kubernetes object that manages a group of Pods. It ensures automatic recovery, rolling updates, and scalability.

Setting Up Your Kubernetes Environment

Prerequisites

Before we start, make sure you have the following installed:

• Windows with WSL2 (or a Linux-based system)

• kubectl (Kubernetes command-line tool)

• Minikube (a tool to run Kubernetes locally)

Installing kubectl

Refer to the Kubernetes documentation for installation steps. On Linux, use the following commands:

curl -LO "https://dl.k8s.io/release/$(curl -L -s https://dl.k8s.io/release/stable.txt)/bin/linux/amd64/kubectl"
sudo install -o root -g root -m 0755 kubectl /usr/local/bin/kubectl
kubectl version --client

Installing Minikube

Follow the Minikube documentation for installation instructions. To start a Minikube cluster, use:

minikube start

Verify that Minikube is running:

minikube status

Deploying an Application

Creating a Pod

Create a configuration file for a simple Nginx pod:

nano nginx-pod.yaml

Paste the following YAML:

apiVersion: v1
kind: Pod
metadata:
  name: nginx
  labels:
    app: nginx
spec:
  containers:
  - name: nginx
    image: nginx:latest
    ports:
    - containerPort: 80

Deploy the pod:

kubectl apply -f nginx-pod.yaml
kubectl get pods

Exposing the Pod

To access the application inside the cluster:

kubectl port-forward pod/nginx 8080:80

Then visit http://localhost:8080 in your browser.

Transitioning to Deployments

Pods alone do not offer resilience. If a Pod crashes, it won’t restart automatically. This is where Deployments come in.

Creating a Deployment

Create a new file for the Deployment:

nano nginx-deployment.yaml

Paste the following YAML:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
  labels:
    app: nginx
spec:
  replicas: 2
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:latest
        ports:
        - containerPort: 80

Apply the deployment:

kubectl apply -f nginx-deployment.yaml
kubectl get deployments
kubectl get pods

Testing Auto-Healing

Delete a pod manually:

kubectl delete pod <pod_name>

Run the following command on second terminal:

kubectl get pods -w

Conclusion

We started with a simple container, transitioned to Pods, and then leveraged Deployments for auto-healing and scalability. Kubernetes provides powerful features, and Minikube is an excellent tool for learning. Experiment with different configurations and explore Kubernetes further!