nginx-config-optimizer

What this skill does

# Nginx Config Optimizer

Create optimized Nginx configurations for high-performance web serving and reverse proxying.

## Core Workflow

1. **Define architecture**: Reverse proxy, load balancer, or static serving
2. **Configure security**: SSL/TLS, headers, rate limiting
3. **Optimize performance**: Caching, compression, buffers
4. **Setup upstream**: Backend server pools
5. **Add monitoring**: Access logs, metrics
6. **Test configuration**: Validate and reload

## Main Configuration

```nginx
# /etc/nginx/nginx.conf

user nginx;
worker_processes auto;
worker_rlimit_nofile 65535;
pid /run/nginx.pid;

# Load dynamic modules
include /etc/nginx/modules-enabled/*.conf;

events {
    worker_connections 4096;
    multi_accept on;
    use epoll;
}

http {
    # Basic settings
    sendfile on;
    tcp_nopush on;
    tcp_nodelay on;
    keepalive_timeout 65;
    types_hash_max_size 2048;
    server_tokens off;

    # Buffer settings
    client_body_buffer_size 16k;
    client_header_buffer_size 1k;
    client_max_body_size 50m;
    large_client_header_buffers 4 8k;

    # Timeouts
    client_body_timeout 12;
    client_header_timeout 12;
    send_timeout 10;

    # MIME types
    include /etc/nginx/mime.types;
    default_type application/octet-stream;

    # Logging
    log_format main '$remote_addr - $remote_user [$time_local] "$request" '
                    '$status $body_bytes_sent "$http_referer" '
                    '"$http_user_agent" "$http_x_forwarded_for"';

    log_format json escape=json '{'
        '"time_local":"$time_local",'
        '"remote_addr":"$remote_addr",'
        '"request":"$request",'
        '"status":$status,'
        '"body_bytes_sent":$body_bytes_sent,'
        '"request_time":$request_time,'
        '"upstream_response_time":"$upstream_response_time",'
        '"http_referer":"$http_referer",'
        '"http_user_agent":"$http_user_agent"'
    '}';

    access_log /var/log/nginx/access.log json;
    error_log /var/log/nginx/error.log warn;

    # Gzip compression
    gzip on;
    gzip_vary on;
    gzip_proxied any;
    gzip_comp_level 5;
    gzip_min_length 256;
    gzip_types
        application/atom+xml
        application/javascript
        application/json
        application/ld+json
        application/manifest+json
        application/rss+xml
        application/vnd.geo+json
        application/vnd.ms-fontobject
        application/x-font-ttf
        application/x-web-app-manifest+json
        application/xhtml+xml
        application/xml
        font/opentype
        image/bmp
        image/svg+xml
        image/x-icon
        text/cache-manifest
        text/css
        text/plain
        text/vcard
        text/vnd.rim.location.xloc
        text/vtt
        text/x-component
        text/x-cross-domain-policy
        text/xml;

    # Brotli compression (if module available)
    # brotli on;
    # brotli_comp_level 6;
    # brotli_types text/plain text/css application/json application/javascript;

    # SSL settings
    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_prefer_server_ciphers on;
    ssl_ciphers ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384;
    ssl_session_cache shared:SSL:10m;
    ssl_session_timeout 1d;
    ssl_session_tickets off;
    ssl_stapling on;
    ssl_stapling_verify on;

    # Security headers (global)
    add_header X-Frame-Options "SAMEORIGIN" always;
    add_header X-Content-Type-Options "nosniff" always;
    add_header X-XSS-Protection "1; mode=block" always;
    add_header Referrer-Policy "strict-origin-when-cross-origin" always;

    # Rate limiting zones
    limit_req_zone $binary_remote_addr zone=general:10m rate=10r/s;
    limit_req_zone $binary_remote_addr zone=api:10m rate=100r/s;
    limit_req_zone $binary_remote_addr zone=login:10m rate=5r/m;
    limit_conn_zone $binary_remote_addr zone=addr:10m;

    # Proxy cache
    proxy_cache_path /var/cache/nginx levels=1:2 keys_zone=STATIC:10m inactive=7d use_temp_path=off max_size=1g;

    # Include site configs
    include /etc/nginx/conf.d/*.conf;
    include /etc/nginx/sites-enabled/*;
}
```

## Reverse Proxy Configuration

```nginx
# /etc/nginx/sites-available/app.conf

upstream backend {
    least_conn;
    keepalive 32;

    server 10.0.1.10:3000 weight=5;
    server 10.0.1.11:3000 weight=5;
    server 10.0.1.12:3000 weight=5 backup;

    # Health checks (Nginx Plus or OpenResty)
    # health_check interval=5s fails=3 passes=2;
}

upstream api {
    ip_hash;
    keepalive 64;

    server 10.0.2.10:8080 max_fails=3 fail_timeout=30s;
    server 10.0.2.11:8080 max_fails=3 fail_timeout=30s;
}

# Redirect HTTP to HTTPS
server {
    listen 80;
    listen [::]:80;
    server_name example.com www.example.com;

    location /.well-known/acme-challenge/ {
        root /var/www/certbot;
    }

    location / {
        return 301 https://$host$request_uri;
    }
}

# Main HTTPS server
server {
    listen 443 ssl http2;
    listen [::]:443 ssl http2;
    server_name example.com www.example.com;

    # SSL certificates
    ssl_certificate /etc/letsencrypt/live/example.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/example.com/privkey.pem;
    ssl_trusted_certificate /etc/letsencrypt/live/example.com/chain.pem;

    # Security headers
    add_header Strict-Transport-Security "max-age=31536000; includeSubDomains; preload" always;
    add_header Content-Security-Policy "default-src 'self'; script-src 'self' 'unsafe-inline'; style-src 'self' 'unsafe-inline'; img-src 'self' data: https:; font-src 'self'; connect-src 'self' https://api.example.com wss://example.com" always;
    add_header Permissions-Policy "camera=(), microphone=(), geolocation=()" always;

    # Rate limiting
    limit_req zone=general burst=20 nodelay;
    limit_conn addr 10;

    # Root and error pages
    root /var/www/html;
    error_page 500 502 503 504 /50x.html;

    # Static files with caching
    location /static/ {
        alias /var/www/static/;
        expires 1y;
        add_header Cache-Control "public, immutable";
        access_log off;
    }

    # Next.js static files
    location /_next/static/ {
        alias /var/www/app/.next/static/;
        expires 1y;
        add_header Cache-Control "public, immutable";
        access_log off;
    }

    # Proxy to backend
    location / {
        proxy_pass http://backend;
        proxy_http_version 1.1;

        # Headers
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header X-Forwarded-Host $host;
        proxy_set_header X-Forwarded-Port $server_port;

        # WebSocket support
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";

        # Keepalive
        proxy_set_header Connection "";

        # Timeouts
        proxy_connect_timeout 60s;
        proxy_send_timeout 60s;
        proxy_read_timeout 60s;

        # Buffering
        proxy_buffering on;
        proxy_buffer_size 4k;
        proxy_buffers 8 4k;
        proxy_busy_buffers_size 8k;

        # Cache settings for specific responses
        proxy_cache STATIC;
        proxy_cache_valid 200 1h;
        proxy_cache_valid 404 1m;
        proxy_cache_bypass $http_cache_control;
        add_header X-Cache-Status $upstream_cache_status;
    }

    # API endpoints
    location /api/ {
        limit_req zone=api burst=50 nodelay;

        proxy_pass http://api/;
        proxy_http_version 1.1;

        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header Connection "";

        # Longer timeout for API
        proxy_read_timeout 120s;

        # No caching for API
        proxy_cache off;
        add_