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

Inception

Description

Inception is a system administration project that uses Docker and Docker Compose to deploy a complete web infrastructure inside a virtual machine. The stack includes an NGINX reverse proxy with TLS, a WordPress application served by php-fpm, and a MariaDB database — each running in its own isolated container.

The goal is to understand containerization, service orchestration, networking, and persistent storage through hands-on practice.

Design Choices

• Base image: Debian Bookworm (penultimate stable release) for all containers.
• Secrets management: Docker secrets mounted as files at /run/secrets/, never embedded in Dockerfiles or images.
• Networking: A dedicated Docker bridge network (inception) connects all services. NGINX is the sole entry point on port 443 with TLS.
• Volumes: Named volumes with local driver, data stored on the host at /home/ezohin/data/.

Virtual Machines vs Docker

Aspect	Virtual Machines	Docker Containers
Isolation	Full OS-level (hypervisor)	Process-level (shared kernel)
Startup	Minutes	Seconds
Size	GBs (full OS)	MBs (only app + deps)
Performance	Overhead from emulation	Near-native
Use case	Full OS environments	Microservices, isolated apps

Secrets vs Environment Variables

Aspect	Docker Secrets	Environment Variables
Storage	Encrypted, mounted as files in /run/secrets/	Plain text in container env
Security	Not visible in docker inspect	Visible in docker inspect
Best for	Passwords, API keys, tokens	Non-sensitive config (domain, ports)

Docker Network vs Host Network

Aspect	Docker Bridge Network	Host Network
Isolation	Containers have their own IP space	Shares host's network stack
Port mapping	Explicit port publishing	No mapping needed
Security	Better isolation between services	Less isolation
DNS	Built-in service discovery	No container DNS

Docker Volumes vs Bind Mounts

Aspect	Named Volumes	Bind Mounts
Management	Managed by Docker	Managed by user
Portability	Easier to back up and migrate	Tied to host path
Performance	Optimized by Docker	Depends on host filesystem
Use case	Production data persistence	Development (live code reload)

Instructions

Prerequisites

• A Virtual Machine running Debian/Ubuntu
• Docker and Docker Compose installed
• make installed

Setup

1. Clone the repository
2. Create the secrets files in secrets/:
   • credentials.txt — WordPress admin/user password
   • db_password.txt — MariaDB user password
   • db_root_password.txt — MariaDB root password
3. Create the .env file in srcs/ (see .env.example)
4. Add your domain to /etc/hosts:

   127.0.0.1 ezohin.42.fr
   

5. Build and run:

   make

Available Commands

Command	Description
make	Build and start all services
make down	Stop and remove containers
make clean	Remove containers and images
make fclean	Full cleanup including volumes and data
make re	Full rebuild
make logs	Follow container logs
make status	Show running containers

Resources

• Docker Documentation
• Docker Compose Reference
• NGINX Documentation
• WordPress CLI
• MariaDB Knowledge Base
• Dockerfile Best Practices
• Docker Secrets

AI Usage

AI tools were used to assist with:

• Generating configuration file templates (NGINX, MariaDB, php-fpm)
• Writing entrypoint scripts for container initialization
• Creating documentation (README, USER_DOC, DEV_DOC)
• Debugging Docker Compose configuration

All AI-generated content was reviewed, tested, and understood before integration.