How to configure CDN scheduling using Nginx_geo module

Syntax of geo directive: geo [$address] $variable { ... }
default value: -
Configuration section: http

Add the following configuration to the /usr/local/nginx/conf/nginx.conf file geo $geo {
    ranges; #Use the address in the form of address segments, this parameter must be placed first default dn;
    include ip_geo.conf;
  }

    upstream wuhan.server {
      server 192.168.155.98:8081;
    }

    upstream shanghai.server {
      server 192.168.155.98:8082;
    }

    upstream shenzhen.server {
      server 192.168.155.98:8083;
    }

    upstream dn.server {
      server 192.168.155.98:8084;
    }

 server {
    listen 80;
    server_name 192.168.155.98 jiaoyu.media.cloudp.cc;
      root html;
      index index.html index.htm;
    location ~* \.xml$ {
      root /data/video;
    }
    location / {
      proxy_redirect off;
      proxy_set_header Host $host;
      proxy_set_header X-Real-IP $remote_addr;
      proxy_set_header X-Forwarded-For 
      $proxy_add_x_forwarded_for;
      proxy_pass http://$geo.server$request_uri;
    }
  }

  server {
    listen 8081;
    server_name 192.168.155.98;
    location / {
      rewrite ^ $scheme://192.168.155.106$request_uri? permanent;
    }
  }

  server {
    listen 8082;
    server_name 192.168.155.98;
    location / {
        rewrite ^ $scheme://192.168.155.107$request_uri? permanent;
    }
  }

server {
    listen 8083;
    server_name 192.168.155.98;
    location / {
        rewrite ^ $scheme://192.168.155.109$request_uri? permanent;
    }
  }

  server {
    listen 8084;
    server_name 192.168.155.98;
    location / {
        rewrite ^ $scheme://jiaoyu.dn.cloudp.cc$request_uri? permanent;
    }
}

vim /usr/local/nginx/conf/ip_geo.conf

192.168.128.6-192.168.128.10 wuhan;
192.168.128.11-192.168.128.15 shanghai;
192.168.128.16-192.168.128.20 shenzhen;