Trisul's Blog

Docker has revolutionized the way we build, ship, and run applications. If you’re new to Docker, this guide will help you understand the basics, set up your first container, and see why Docker is a must-have for modern cloud and network deployments.

What is Docker and Why Use It?

Docker is an open-source platform designed to simplify application development and deployment. It allows developers to package applications and their dependencies into lightweight, portable containers that can run consistently across various environments.
Benefits:

• Portability: Containers run anywhere Docker is installed, from your laptop to a production server.
• Efficiency: Uses fewer resources than virtual machines.
• Scalability: Easily scale apps with orchestration tools.
• Isolation: Each container runs independently, avoiding conflicts.

Installing Docker

Windows/Mac: Download Docker Desktop from docker.com.
Linux: Use your package manager. For example (Ubuntu):

sudo apt update
sudo apt install -y docker.io
sudo systemctl start docker
sudo systemctl enable docker

Verify installation:

docker --version

Core Concepts

• Images: Immutable templates that define how a container is built.
• Containers: Running instances of Docker images.
• Dockerfile: Script that automates the creation of Docker images.
• Volumes: Persist data generated by containers.
• Networks: Enable communication between containers.

Basic Docker Commands

Working with Images:

docker pull <image_name>
docker images
docker rmi <image_id>

Working with Containers:

docker run -d -p 8080:80 <image_name>
docker ps -a
docker stop <container_id>
docker rm <container_id>
docker exec -it <container_id> bash
docker inspect <container_id>
docker logs <container_id>

Your First Docker Project: Simple Web Server

Let’s create a simple web server using Nginx. First, create an index.html file with some content. Then, use this Dockerfile:

FROM nginx:alpine
COPY ./index.html /usr/share/nginx/html
EXPOSE 80

Build and run your container:

docker build -t my-nginx-app .
docker run -d -p 8080:80 my-nginx-app

Now, open http://localhost:8080 in your browser to see your web page running in Docker!

Why Docker Matters for Real Projects

As a network and cloud engineer, I use Docker to deploy Node.js/Express apps, Vite.js frontends, and more. Docker makes it easy to automate deployments and keep environments consistent across dev, staging, and production.