nginx conf for balancer

gistfile1.txt

user nginx;
worker_processes auto;
worker_rlimit_nofile 10000;
pid /var/run/nginx.pid;

events {
    worker_connections 4000;
    multi_accept on;
    use epoll;
}

http {

    ##
    # Basic Settings
    ##

    sendfile on;
    tcp_nopush on;
    tcp_nodelay on;
    keepalive_requests 1000;
    keepalive_timeout 75 20;
    reset_timedout_connection on;
    client_body_timeout 60;
    send_timeout 10;
    types_hash_max_size 2048;
    server_tokens off;
    # https://medium.com/@getpagespeed/how-to-remove-the-server-header-in-nginx-e74c7b431b
    # more_clear_headers Server;
    # cache informations about FDs, frequently accessed files
    # can boost performance, but you need to test those values
    # open_file_cache max=200 inactive=20s;
    # open_file_cache_valid 30s;
    # open_file_cache_min_uses 2;
    # open_file_cache_errors on;
    # server_names_hash_bucket_size 64;
    # server_name_in_redirect off;

    #
    # Override some buffer limitations, will prevent DDOS too.
    #
    client_body_buffer_size 10K;
    client_header_buffer_size 4k;
    client_max_body_size 16m;
    large_client_header_buffers 8 8k;
    request_pool_size               4k;
    output_buffers 1 32k;
    postpone_output 1460;

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

    ##
    # SSL Settings
    ##

    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_prefer_server_ciphers on;


    map $sent_http_content_type $x_ua_compatible {
        ~*text/html "IE=edge";
    }

    # map $sent_http_content_type $x_xss_protection {
    # ~*text/html "1; mode=block";
    # }

    # map $sent_http_content_type $x_frame_options {
    # ~*text/html DENY;
    # }


    ##
    # Logging Settings
    ##
    log_format extended_json escape=json
        '{'
        '"event_datetime": "$time_iso8601", '
        '"server_name": "$server_name", '
        '"remote_addr": "$remote_addr", '
        '"remote_user": "$remote_user", '
        '"http_x_real_ip": "$http_x_real_ip", '
        '"status": "$status", '
        '"scheme": "$scheme", '
        '"request_method": "$request_method", '
        '"request_uri": "$request_uri", '
        '"server_protocol": "$server_protocol", '
        '"body_bytes_sent": "$body_bytes_sent", '
        '"http_referer": "$http_referer", '
        '"http_user_agent": "$http_user_agent", '
        '"request_bytes": "$request_length", '
        '"request_time": "$request_time", '
        '"upstream_addr": "$upstream_addr", '
        '"upstream_response_time": "$upstream_response_time", '
        '"hostname": "$hostname", '
        '"host": "$host"'
        '}';


    #   access_log /var/log/nginx/access.log;
        # error_log /var/log/nginx/error.log;

      ##
      # Gzip Settings
      ##

    gzip  on;
    gzip_static on;
    gzip_comp_level 5;
    gzip_min_length 1024;
    gzip_proxied     any;
    gzip_vary on;
    gzip_proxied expired no-cache no-store private auth;
    gzip_types application/atom+xml application/geo+json application/javascript application/x-javascript application/json application/ld+json application/manifest+json application/rdf+xml application/rss+xml application/vnd.ms-fontobject application/wasm application/x-web-app-manifest+json application/xhtml+xml application/xml application/font-woff2 application/x-font-woff application/font-woff application/x-font-ttf font/eot font/otf font/ttf image/bmp image/svg+xml text/cache-manifest text/calendar text/markdown text/plain text/xml text/vcard text/vnd.rim.location.xloc text/vtt text/x-component text/x-cross-domain-policy;

    gzip_disable "MSIE [1-6]\.(?!.*SV1)";

    map $sent_http_content_type $expires {
        "text/html"                 epoch;
        "text/html; charset=utf-8"  epoch;
        default                     off;
    }

    server_names_hash_max_size 8192;
    #ignore_invalid_headers  on;
    server_name_in_redirect off;

    proxy_buffer_size       8k;
    proxy_buffers           8 64k;
    proxy_connect_timeout   1000;
    proxy_read_timeout      12000;
    proxy_send_timeout      12000;

    proxy_cache_path /var/cache/nginx levels=2 keys_zone=pagecache:5m inactive=10m max_size=50m;

    real_ip_header          X-Real-IP;
    proxy_set_header        Host            $host;
    proxy_set_header        X-Real-IP       $remote_addr;
    proxy_set_header        X-Forwarded-For $proxy_add_x_forwarded_for;

    allow all;


    include /etc/nginx/conf.d/*.conf;
    include /etc/nginx/sites-enabled/*;

    error_log /dev/stdout crit;
    # error_log /dev/stdout warn;
    access_log off;
  # access_log /dev/stdout extended_json;
}