nginx.conf - lost request research

nginx.conf

worker_processes  6;

worker_rlimit_nofile 10240;

timer_resolution 500ms;

pid /var/run/nginx.pid;

events {
    worker_connections 10240;

    # Accept as many connections as possible, after nginx gets notification about a new connection.
    # May flood worker_connections, if that option is set too low.
    multi_accept on;

    use epoll;
}

http {
    include       mime.types;
    default_type  application/octet-stream;

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

    sendfile       on;
    tcp_nopush     on;

    keepalive_timeout  65;
    keepalive_requests 2000;
    reset_timedout_connection on;
    client_body_timeout 10;
    client_header_timeout 10;
    client_header_buffer_size 128;
    send_timeout 2;

    # Use Host header instead of  server_name for redirects:
    server_name_in_redirect off;


    #Don’t tell the world the intimate details of our nginx installation
    server_tokens off;

    # Caches information about open FDs, freqently accessed files.
    # http://dak1n1.com/blog/12-nginx-performance-tuning
    # Changing this setting, in my environment, brought performance up from 560k req/sec, to 904k req/sec.
    # I recommend using some varient of these options, though not the specific values listed below.
    open_file_cache max=1000 inactive=20s; 
    open_file_cache_valid 30s; 
    open_file_cache_min_uses 2;
    open_file_cache_errors on;


    gzip  on;
    gzip_http_version 1.0;
    gzip_disable      "MSIE [1-6]\.(?!.*SV1)";
    gzip_comp_level   2;
    gzip_min_length 0;
    gzip_proxied expired no-cache no-store private auth;
    gzip_buffers 4 16k;
    gzip_types        application/json text/plain text/css application/x-javascript text/xml application/xml application/rss+xml text/javascript;

    upstream app {
      # Path to Unicorn SOCK file, as defined previously
      server unix:/var/sockets/unicorn.sock fail_timeout=0;
    }

    server {
        listen 443 ssl;
        server_name _;
        
        ssl on;
        ssl_certificate /usr/local/nginx/ssl/webapp.crt;
        ssl_certificate_key /usr/local/nginx/ssl/webapp.key;

        # SSL Settings
        # http://nginx.org/en/docs/http/configuring_https_servers.html
        ssl_session_cache   shared:SSL:10m;
        ssl_session_timeout 10m;

        ssl_prefer_server_ciphers on;
        ssl_protocols  SSLv3 TLSv1 TLSv1.1 TLSv1.2;
        ssl_ciphers ECDHE-RSA-AES256-SHA384:AES256-SHA256:RC4:HIGH:!MD5:!aNULL:!EDH:!AESGCM;

        access_log  logs/webapp.access.ssl.log  main;
        error_log   logs/webapp.error.ssl.log notice;

        # Application root, as defined previously
        root /var/www/webapp/public;

        try_files $uri/index.html $uri @app;

        location @app {
                proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
                proxy_set_header X-Real-IP  $remote_addr;
                proxy_set_header Host $http_host;
                proxy_set_header X-FORWARDED-PROTO https;
                proxy_redirect off;
                proxy_pass http://app;
        }

        location = /favicon.ico {
            alias    /var/www/webapp/public/assets/scc_favicon.ico;
        }

        location = /assets/favicon.ico {
            alias    /var/www/webapp/public/assets/scc_favicon.ico;
        }


        error_page 500 502 503 504 /500.html;
        client_max_body_size 20m;
        keepalive_timeout 10;

        # Headersmore Nginx Fingerprinting header removal
        #********************************************************************
        #
        # Clear Server Header
        more_clear_headers 'Server';
       
        # Clear X-Powered-By header
        more_clear_headers 'X-Powered-By';
    }

    server {
        listen 80;
        server_name _;
        
        access_log  logs/webapp.access.log  main;
        error_log   logs/webapp.error.log notice;

        # Application root, as defined previously
        root /var/www/webapp/public;

        try_files $uri/index.html $uri @app;

        location @app {
                proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
                proxy_set_header X-Real-IP  $remote_addr;
                proxy_set_header Host $http_host;
                proxy_redirect off;
                proxy_pass http://app;
        }

        location = /favicon.ico {
            alias    /var/www/webapp/public/assets/scc_favicon.ico;
        }

        location = /assets/favicon.ico {
            alias    /var/www/webapp/public/assets/scc_favicon.ico;
        }

        error_page 500 502 503 504 /500.html;
        client_max_body_size 20m;
        keepalive_timeout 10;

        # Headersmore Nginx Fingerprinting header removal
        #********************************************************************
        #
        # Clear Server Header
        more_clear_headers 'Server';
       
        # Clear X-Powered-By header
        more_clear_headers 'X-Powered-By';
    }
}