nginx生产配置文件参考 解决http 499 问题，解决银联回调 异常，每次请求第一次失败，第二次成功，每次都要等三分钟，主要添加参数是优化buffer\cache，还有超时时间,

问题排查步骤：

1，查看DNS 【服务器本地DNS、局域网bindDNS，CDN解析，域名映射，NAT等】
2，查看nginx 连接状态，TCP11种状态，是否存在主动丢弃连接
3，查看nginx配置 是否存在优化项，特呗注意 timeout、ignore_client_abort，fastcgi端口跳转等等

##--------------------------------------------------------------------------
user  www www;
worker_processes 4;
error_log  /home/logs/nginx_error.log notice;
pid        /var/run/nginx.pid;
worker_rlimit_nofile 6553;##--------------------------------------------------------------------------
events {use epoll;worker_connections 5120;multi_accept on;}
##--------------------------------------------------------------------------
http {include       mime.types;
#include       secure/limit_zone.conf;default_type  application/octet-stream;server_tokens off;server_names_hash_bucket_size 128;client_header_buffer_size 512k;client_body_buffer_size 1024k;large_client_header_buffers 4 32k;client_max_body_size 50m;sendfile   on;tcp_nopush on;keepalive_timeout 300;tcp_nodelay on;
##--------------------------------------------------------------------------fastcgi_connect_timeout 300;fastcgi_send_timeout 300;fastcgi_read_timeout 300;fastcgi_ignore_client_abort on;fastcgi_buffer_size 512k;fastcgi_buffers 6 512k;fastcgi_busy_buffers_size 512k;fastcgi_temp_file_write_size 512k;fastcgi_next_upstream error timeout invalid_header http_500 http_503 http_403;
##--------------------------------------------------------------------------gzip on;gzip_min_length  1k;gzip_buffers     4 16k;gzip_http_version 1.1;gzip_comp_level 4;gzip_types     text/plain application/javascript application/x-javascript text/javascript text/css application/xml application/xml+rss;gzip_vary on;gzip_proxied   expired no-cache no-store private auth;gzip_disable   "MSIE [1-6]\.";proxy_connect_timeout    3;proxy_read_timeout       60;proxy_send_timeout       60;
###--------------------------------------------------------------------------log_format main '$remote_addr - $remote_user [$time_local] "$request"''$status $body_bytes_sent "$http_referer"''"$http_user_agent" "$http_x_forwarded_for"';
##--------------------------------------------------------------------------
upstream myfastcgi {ip_hash;server 192.168.0.32:9000  weight=1;
}
##--------------------------------------------------------------------------
include       vhost/*.conf;log_format json '{ "@timestamp": "$time_local", ''"@fields": { ''"remote_addr": "$remote_addr", ''"remote_user": "$remote_user", ''"body_bytes_sent": "$body_bytes_sent", ''"request_time": "$request_time", ''"status": "$status", ''"request": "$request", ''"request_method": "$request_method", ''"http_referrer": "$http_referer", ''"body_bytes_sent":"$body_bytes_sent", ''"http_x_forwarded_for": "$http_x_forwarded_for", ''"http_user_agent": "$http_user_agent" } }';access_log  /var/log/nginx/access_json.log  json;
}
##--------------------------------------------------------------------------