NGINX

High-performance web server and reverse proxy.

When to Use

• Reverse proxy for applications
• Load balancing
• SSL termination
• Static file serving

Quick Start

# Basic reverse proxy
server {
    listen 80;
    server_name example.com;

    location / {
        proxy_pass http://localhost:3000;
        proxy_http_version 1.1;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
    }
}

Core Concepts

SSL Configuration

server {
    listen 443 ssl http2;
    server_name example.com;

    ssl_certificate /etc/letsencrypt/live/example.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/example.com/privkey.pem;
    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_ciphers ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256;
    ssl_prefer_server_ciphers off;

    # HSTS
    add_header Strict-Transport-Security "max-age=31536000" always;

    location / {
        proxy_pass http://app;
    }
}

# Redirect HTTP to HTTPS
server {
    listen 80;
    server_name example.com;
    return 301 https://$server_name$request_uri;
}

Load Balancing

upstream app {
    least_conn;
    server 127.0.0.1:3001 weight=3;
    server 127.0.0.1:3002;
    server 127.0.0.1:3003 backup;

    keepalive 32;
}

server {
    location / {
        proxy_pass http://app;
        proxy_http_version 1.1;
        proxy_set_header Connection "";
    }
}

Common Patterns

Caching

proxy_cache_path /var/cache/nginx levels=1:2 keys_zone=app_cache:10m max_size=1g;

server {
    location /api {
        proxy_cache app_cache;
        proxy_cache_valid 200 10m;
        proxy_cache_key "$scheme$request_method$host$request_uri";
        add_header X-Cache-Status $upstream_cache_status;

        proxy_pass http://app;
    }

    location /static {
        alias /var/www/static;
        expires 30d;
        add_header Cache-Control "public, immutable";
    }
}

Rate Limiting

limit_req_zone $binary_remote_addr zone=api:10m rate=10r/s;

server {
    location /api {
        limit_req zone=api burst=20 nodelay;
        proxy_pass http://app;
    }
}

Best Practices

Do:

• Enable gzip compression
• Set proper timeouts
• Use connection keepalive
• Configure proper logging

Don't:

• Expose server version
• Use weak SSL ciphers
• Skip security headers
• Ignore log rotation

Troubleshooting

Issue	Cause	Solution
502 Bad Gateway	Backend down	Check upstream health
504 Timeout	Slow backend	Increase proxy_read_timeout
Permission denied	File permissions	Check nginx user perms

References

• NGINX Documentation
• NGINX Config Generator