This project has been created as part of the 42 curriculum by mamorais.

Inception

Description

Inception is a system administration project focused on building a small web infrastructure using Docker. The objective is to run multiple services inside isolated containers and make them work together as a complete system.

This project includes:

• NGINX (HTTPS server, single entry point)
• WordPress (PHP-FPM only, no web server inside)
• MariaDB (database)

Each service runs in its own container and communicates through a Docker network. The goal is to understand:

• containerization
• service isolation
• secure configuration
• infrastructure orchestration

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Project Architecture

The infrastructure is built using:

• docker-compose.yml → defines services, volumes, networks, and secrets
• Dockerfiles → one for each service: mariadb, wordpress, nginx.
  • srcs/requirements/nginx/Dockerfile
  • srcs/requirements/wordpress/Dockerfile
  • srcs/requirements/mariadb/Dockerfile
• Initialization scripts:
  • srcs/requirements/mariadb/tools/init_db.sh for MariaDB
  • srcs/requirements/wordpress/tools/init_wp.sh for WordPress
  • srcs/requirements/nginx/tools/entrypoint.sh for NGINX

All services are connected through a private Docker network and only NGINX exposes port 443 to the outside.

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Project Structure

inception/
├── Makefile
├── README.md
├── USER_DOC.md
├── DEV_DOC.md
├── secrets
│   ├── credentials.txt
│   ├── db_password.txt
│   ├── db_root_password.txt
│   └── wp_user_password.txt
└── srcs
    ├── docker-compose.yml
    └── requirements
        ├── mariadb
        │   ├── Dockerfile
        │   └── tools
        │       └── init_db.sh
        ├── nginx
        │   ├── conf
        │   │   └── default.conf
        │   ├── Dockerfile
        │   └── tools
        │       └── entrypoint.sh
        └── wordpress
            ├── Dockerfile
            └── tools
                └── init_wp.sh

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Instructions

Requirements (VM)

• Run inside a Virtual Machine.
• Install:
  • Docker Engine
  • Docker Compose plugin

Domain configuration

Add the project domain to /etc/hosts on the VM host system:

echo "127.0.0.1 mamorais.42.fr" | sudo tee -a /etc/hosts

Secrets

Passwords are stored in secrets/ and mounted into containers as Docker secrets under /run/secrets/:

• db_root_password.txt → MariaDB root password
• db_password.txt → WordPress database user password
• credentials.txt → WordPress admin password
• wp_user_password.txt → WordPress user password

Passwords must not be hard-coded inside Dockerfiles or committed to the repository.

Environment variables

Non-sensitive configuration lives in srcs/.env.

The WordPress admin username must not contain admin, administrator, or similar names.

Build & Run

From the repository root:

make

Stop

make down

Help

make help

Technical Choices

Virtual Machines vs Docker

• Virtual Machines

  • Run a full operating system
  • Higher resource usage
  • Slower startup

• Docker

  • Lightweight containers
  • Faster startup
  • Easier to reproduce environments

This project uses Docker to efficiently manage multiple services while running inside a Virtual Machine as required by the subject.

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Secrets vs Environment Variables

• Environment Variables

  • Easy to configure
  • Not secure for sensitive data

• Docker Secrets

  • Stored as files in /run/secrets/
  • More secure for passwords

This project uses environment variables for configuration and Docker secrets for sensitive data.

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Docker Network vs Host Network

• Host Network

  • No isolation
  • Less secure

• Docker Network (bridge)

  • Isolated communication
  • Containers communicate using service names

This project uses a bridge network for secure communication between services.

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Docker Volumes vs Bind Mounts

• Bind Mounts

  • Direct mapping to host filesystem
  • Requires manual management

• Docker Volumes

  • Managed by Docker
  • More portable and easier to handle

This project uses persistent storage located at:

• /home/<your-user>/data/docker/

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Resources

• Docker Documentation (containers, images, volumes, networks, Compose)
• Docker Compose Documentation
• NGINX Documentation (TLS/SSL, reverse proxy, FastCGI)
• WordPress Documentation + php-fpm
• WP-CLI Documentation
• MariaDB Documentation

How AI was used

AI (ChatGPT) was used as a learning assistant to:

• Clarify the subject requirements.
• Review and improve documentation structure.
• Suggest validation ideas and sanity checks (connectivity checks, HTTPS-only verification).

All final implementation, configuration, and testing decisions were made and executed by the project author.

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Local Configuration

The repository intentionally does not include real environment variables or credentials.

Before running the project:

cp srcs/.env.example srcs/.env

Then configure the values for your local environment.

Create the required secret files inside secrets/:

secrets/
├── credentials.txt
├── db_password.txt
├── db_root_password.txt
└── wp_user_password.txt

Real .env and secret files are excluded from Git.

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Public Project Showcase

A public technical showcase of this project is being prepared to demonstrate the architecture, infrastructure decisions and container topology without exposing credentials.

The original Inception implementation remains Docker-based and is designed to run inside a Linux virtual machine as required by the 42 project.