Docker & Kubernetes in simple Guide

Docker & Kubernetes Guide

Chapter 1: Dockers & Containers Introduction

What is Docker?

Explanation: Docker is like a magic box that can pack your app and all its stuff so it works the same anywhere you run it.

Practical Example: Run docker run hello-world in your terminal to see a simple message from Docker.

What are Containers?

Explanation: Containers are like small, portable houses for your apps. They include everything an app needs to run, so you can move the house anywhere, and it will work just fine.

Practical Example: Imagine you have a house with all the furniture and kitchen appliances. You can take this house anywhere, and everything inside works perfectly.

Why Use Docker?

 Explanation: Docker makes sure your app runs the same way everywhere. It's like having a travel-ready suitcase for your app that keeps everything neat and organized.

Practical Example: Your app works on your laptop and the same app works the same way on your friend's computer, or on a big server, without changing anything.

Chapter 2: Installation and Architecture of Docker

Installation of Docker

 Explanation: Installing Docker is like setting up the magic box on your computer so you can start using it.

Practical Example: Follow simple steps to install Docker, then check it's working by running docker --version.

Docker Architecture

 Explanation: Docker has three main parts: the engine (which does the work), a way to talk to it (API), and commands you use (CLI). Think of it like a car engine, steering wheel, and dashboard.

Practical Example: When you use docker run, the engine does the work, the API processes the command, and the CLI is what you type.

Docker vs. Virtual Machines

 Explanation: Docker containers are like tiny, efficient houses, while virtual machines are like full-sized houses. Containers share some parts with others, making them faster and use fewer resources.

Practical Example: Running a small app in a container uses less space and starts faster compared to running it in a virtual machine.

Chapter 3: Docker Images, Volumes & Networking

Docker Images

 Explanation: Docker images are like blueprints for building containers. They contain all the instructions and files needed.

Practical Example: Use a Dockerfile to create an image that includes a simple web app.

Docker Volumes

 Explanation: Volumes are like external hard drives for your containers. They store data that you want to keep even if the container stops or is removed.

Practical Example: Attach a volume to a container to save data, so it’s still there when you restart the container.

Docker Networking

 Explanation: Docker networking is like setting up a phone line between containers so they can talk to each other.

Practical Example: Connect two containers so a web app in one container can talk to a database in another.

Chapter 4: Registries in Docker

Docker Hub and Other Registries

 Explanation: Docker Hub is like an app store for Docker images. Other registries are like private app stores where you can store your own images.

Practical Example: Push an image to Docker Hub and pull it on another computer to run the same container.

Pushing and Pulling Images

 Explanation: Pushing is like uploading your app to the cloud. Pulling is like downloading it.

Practical Example: Upload your custom Docker image to Docker Hub and download it on a different machine.

Chapter 5: Docker – Orchestration

Introduction to Docker Compose

 Explanation: Docker Compose is like a director that coordinates multiple containers to work together.

Practical Example: Create a docker-compose.yml file to run a web app and database together with one command.

Docker Swarm

 Explanation: Docker Swarm is like having multiple directors for a big show, managing lots of containers across different machines.

Practical Example: Set up Docker Swarm to run a web app on multiple computers working together.

Chapter 6: Kubernetes Introduction

What is Kubernetes?

 Explanation: Kubernetes is like a super manager for containers, making sure they run smoothly, can handle lots of work, and stay healthy.

Practical Example: Use Minikube to set up a small Kubernetes cluster and deploy a web app.

Kubernetes Components

 Explanation: Kubernetes has many parts, like nodes (workers), pods (smallest units), services (networking), and more, all working together to manage containers.

Practical Example: Deploy an app on Kubernetes and expose it with a service to make it accessible.