Deploying Your First Web Server with Docker: A Beginner's Guide.

NGINX WEB SERVER WITH DOCKER.
Here's a straightforward guide to creating a Nginx web server with Docker. This is ideal for beginners looking to understand the basics of Docker and web servers.

---

Building a Ngnix Web Server with Docker:
If you're venturing into DevOps, understanding Docker is essential. Docker lets you package applications and their dependencies into a single container, allowing for quick deployment and consistency across different environments. Here's a step-by-step guide to creating a Nginx web server in Docker.

---

Prerequisites:
Before we start, make sure you have:
Docker installed on your machine (check the installation by running docker -version).
Basic understanding of web servers (HTML/CSS is a plus).

---

Step 1: Write a Simple HTML File.
Let's create a simple webpage to serve as our content.

1. Create a directory for your project: mkdir docker-project-1 cd docker-project-1
2. Inside this directory, create an index.html file

touch index.html
nano index.html

This file will be our web server's home page.

---

Step 2: Create a Dockerfile:
A Dockerfile is a script that contains instructions for building a Docker image. This file will tell Docker how to set up our web server environment.
Inside your project directory, create a file named Dockerfile.
Add the below content to the Dockerfile:

Here's a breakdown of each line in the Dockerfile:

• FROM nginx:alpine: This line tells Docker to use the official Nginx image, which includes a lightweight Nginx server built on the Alpine Linux distribution.
• COPY index.html /usr/share/nginx/html/: This line copies our index.html file into the default directory Nginx serves files from.
• EXPOSE 80: This exposes port 80 on the container, allowing us to access the web server.

---

Step 3: Build the Docker Image:
With the Dockerfile and index.html file in place, let's build the Docker image.
Run the following command in the terminal:
docker build -t my-ngix-app .

Here's what this command does:

• docker build: Builds a Docker image from a Dockerfile.
• -t my-nginx-app: Tags the image with a name, my-nginx-app, making it easier to refer to later.
• .: Tells Docker to use the current directory as the build context (this is where Docker will look for the Dockerfile).

View the images with the below command:
docker images
Docker will pull the Nginx image if you don't have it already and then build your custom image with the specified configuration.

---

Step 4: Run the Docker Container.
Once the image is ready, you can run it as a container.
Run the following command:
docker run -d -p 8080:80 my-nginx-app

This command does a few things:

• docker run: Creates and starts a new container.
• -d: Runs the container in detached mode, so it runs in the background.
• -p 8080:80: Maps port 8080 on your local machine to port 80 on the container (where Nginx is listening).
• my-nginx-app: Specifies the image to use.

---

Step 5: Test Your Web Server.
Now, open a web browser and go to http://localhost:8080. You should see the "Hello, Oluchukwu!" message from your index.html file.

Congratulations - you've successfully set up a Nginx web server in Docker!

---

Step 6: Stopping the Container.
When you're done, you can stop the container with the following command:
docker ps -a # Find the container ID if you need to
docker stop <container_id>
Remove the container with the below command:
docker rm <container_id>
Then, remove the image with the below command:
docker rmi <images id>

---

Wrapping Up.
You now have a Nginx web server running in Docker! This setup is easy to expand for more complex web applications by:
Using different web servers or application stacks.
Incorporating dynamic content with languages like Python, Node.js, or PHP.
Adding volume mounting to manage files outside the container.
 
Containers offer a consistent, isolated environment, making development and deployment easier. Try experimenting with other configurations, and get comfortable with Docker's potential in DevOps.

---

Final Thoughts:
Docker is a powerful tool for simplifying application deployment. By understanding how to containerize even the simplest applications, you're building a foundation that will help you in any DevOps or cloud-based role.