nginx.conf

user nginx;
worker_processes auto;
error_log /var/log/nginx/error.log warn;
pid /var/run/nginx.pid;

events {
    worker_connections 1024;
}

http {
    include /etc/nginx/mime.types;
    default_type application/octet-stream;
    log_format main '$remote_addr - $remote_user [$time_local] "$request" '
                    '$status $body_bytes_sent "$http_referer" '
                    '"$http_user_agent" "$http_x_forwarded_for"';
    access_log /var/log/nginx/access.log main;
    sendfile on;
    tcp_nopush on;
    tcp_nodelay on;
    keepalive_timeout 65;
    types_hash_max_size 2048;

    # SSL configuration
    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:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384;
    ssl_session_timeout 1d;
    ssl_session_cache shared:SSL:50m;
    ssl_session_tickets off;
    ssl_stapling on;
    ssl_stapling_verify on;
    resolver 8.8.8.8 8.8.4.4 valid=300s;
    resolver_timeout 5s;

    # Define upstream servers for load balancing
    upstream app_servers {
        least_conn;  # Use least connections algorithm for load balancing
        
        # Add all 10 servers
        server localhost:7850;
        server localhost:7851;
        server localhost:7852;
        server localhost:7853;
        server localhost:7854;
        server localhost:7855;
        server localhost:7856;
        server localhost:7857;
        server localhost:7858;
        server localhost:7859;
    }

    # Redirect HTTP to HTTPS
    server {
        listen 80;
        server_name 158.130.50.41;  # Change this to your domain name
        return 301 https://$server_name$request_uri;
    }

    # HTTPS server configuration
    server {
        listen 443 ssl http2;
        server_name 158.130.50.41;  # Change this to your domain name

        # SSL certificate paths
        ssl_certificate /etc/nginx/ssl/cert.pem;
        ssl_certificate_key /etc/nginx/ssl/key.pem;

        # WebSocket support
        location / {
            proxy_pass http://app_servers;
            proxy_http_version 1.1;
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection "upgrade";
            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-Ssl on;
            
            # Timeout settings for WebSocket
            proxy_read_timeout 300s;
            proxy_send_timeout 300s;
            proxy_connect_timeout 75s;
            
            # Buffer settings
            proxy_buffering off;
            proxy_buffer_size 128k;
            proxy_buffers 4 256k;
            proxy_busy_buffers_size 256k;
        }

        # Health check endpoint
        location /health {
            access_log off;
            return 200 'healthy\n';
        }

        # Security headers
        add_header Strict-Transport-Security "max-age=63072000" always;
        add_header X-Frame-Options DENY;
        add_header X-Content-Type-Options nosniff;
        add_header X-XSS-Protection "1; mode=block";
    }
}