What it does
Nginx receives requests first, then forwards them to the right app or service based on path, host, or rule.
Lesson 19
Reverse proxy with Nginx
This page explains how one front-facing service can receive browser traffic and then forward requests to the correct container behind the scenes.
Why it helps
It centralizes domains, SSL, routing, and port management so app containers can stay focused on application logic.
Common pattern
Browser traffic often hits Nginx on port 80 or 443, and Nginx forwards traffic to internal containers on their private ports.
Single app routing
Browser
Nginx
App container
Split routing
/ goes to frontend
/api goes to backend
One domain, multiple services
Why not expose every container directly
- Port handling becomes messy fast.
- Domain setup becomes harder to organize.
- SSL setup gets repeated in multiple places.
- Traffic flow becomes less predictable.
Where Nginx adds value
- Routing requests to frontend or backend.
- Serving static files efficiently.
- Acting as the public web entry point.
- Handling HTTPS before traffic reaches the app.
Simple proxy idea
Browser -> nginx:80
nginx -> frontend:3000
nginx -> backend:5000
The user only sees the public web address. Internal container ports remain hidden behind the proxy.
Beginner confusion to avoid
Nginx is not replacing your backend. It is standing in front of it, guiding incoming traffic to the correct destination.
Reverse proxy memory guide
Nginx is the front desk
Requests arrive there first.
Requests arrive there first.
Your app stays behind it
The app does not need to directly manage every public traffic concern.
The app does not need to directly manage every public traffic concern.
Routing becomes cleaner
One domain can serve multiple containers.
One domain can serve multiple containers.
Public ports and internal ports stay separated
That makes the overall setup easier to control.
That makes the overall setup easier to control.
Next page: Lesson 20 brings frontend, backend, and database together into one full stack Docker workflow.