Docker and Kubernetes for Beginners: A Practical Guide

📌Introduction

Containerization has revolutionized how we build, ship, and run applications. This guide will get you started with Docker and Kubernetes.

📌What is Docker?

Docker packages your application with all dependencies:

Consistent environments

Easy sharing

Fast startup

Resource isolation

📌Docker Basics

Key Commands

# Build an image
docker build -t myapp .
# Run a container
docker run -p 8080:8080 myapp
# List containers
docker ps
# Stop a container
docker stop <container-id>

Dockerfile Example

FROM openjdk:17-slim
COPY target/app.jar app.jar
EXPOSE 8080
ENTRYPOINT ["java", "-jar", "app.jar"]

📌What is Kubernetes?

Kubernetes orchestrates containers at scale:

Automatic scaling

Self-healing

Rolling updates

Service discovery

📌Kubernetes Basics

Key Concepts

Pod: Smallest deployable unit

Deployment: Manages pod replicas

Service: Network endpoint for pods

Ingress: External access to services

Simple Deployment

apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp
spec:
  replicas: 3
  selector:
    matchLabels:
      app: myapp
  template:
    metadata:
      labels:
        app: myapp
    spec:
      containers:
      - name: myapp
        image: myapp:1.0
        ports:
        - containerPort: 8080

📌Getting Started

1Install Docker Desktop

2Enable Kubernetes

3Deploy your first app

4Scale and update

5Monitor and debug

Our Docker and Kubernetes courses take you from beginner to production-ready.