Nginx 反向代理，流量转发到固定内网 IP 方法

主配置文件：

 user  nginx;
 worker_processes  ;

 error_log  /var/log/nginx/error.log warn;
 pid        /var/run/nginx.pid;

 events {
     worker_connections  ;
 }

 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;

     keepalive_timeout  ;

     gzip  on;

 #################

  proxy_connect_timeout ;
     proxy_send_timeout ;
     proxy_read_timeout ;
     proxy_buffer_size 16k;
     proxy_buffers  32k;

     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-For $remote_addr;
     proxy_set_header Connection Close;

     server_names_hash_max_size ;
     server_names_hash_bucket_size ;

     # Default cache parameters for use by virtual hosts 

     # Set the cache path to tmpfs mounted disk, and the zone name 

     # Set the maximum size of the on disk cache to less than the tmpfs file system size 

     proxy_cache_path  ./cache  levels=:  keys_zone=pscms:100m max_size=800m; 

     proxy_temp_path   ./proxy; 

 #############

     include /etc/nginx/conf.d/*.conf;
 }

网站配置文件：

 upstream web_server {
         #sticky;
         server 192.168.203.23;
         server 192.168.203.24;
         server 192.168.203.25;
      #  ip_hash;
     }

 server {
     listen       ;
     server_name  localhost;
     charset utf-;
     access_log  /var/log/nginx/.log  main;

 location / {
 if ( $remote_addr ~* ^(.*)\.(.*)\.(.*)\.$){
                 proxy_pass http://192.168.203.22;
                 break;
         }

             proxy_set_header Host $http_host;
             proxy_redirect     off;
             proxy_pass         http://web_server;
             proxy_set_header   Host             $host;
             proxy_set_header   X-Real-IP        $remote_addr;
             proxy_set_header   X-Forwarded-For $proxy_add_x_forwarded_for;
         }
 }