nginx 根据端口不一样实现负载均衡

upstream www.abc.com {    server www.mynginx.com:91;    server www.mynginx.com:92;    }server {        listen       80;        server_name  www.mynginx.com;        location / {            root   D:/www/mynginx;            index  index.html index.htm index.php;               proxy_pass        http://www.abc.com;                                                proxy_set_header  X-Real-IP  $remote_addr;        }        location ~ \.php$ {            root          D:/www/mynginx;            fastcgi_pass   127.0.0.1:9000;            fastcgi_index  index.php;            fastcgi_param  SCRIPT_FILENAME  $document_root$fastcgi_script_name;            include        fastcgi_params;        }}server {        listen       91;        server_name  www.mynginx.com:91;        location / {            root   D:/www/nginx01;            index  index.html index.htm index.php;        }        location ~ \.php$ {            root          D:/www/nginx01;            fastcgi_pass   127.0.0.1:9000;            fastcgi_index  index.php;            fastcgi_param  SCRIPT_FILENAME  $document_root$fastcgi_script_name;            include        fastcgi_params;        }}server {        listen       92;        server_name  www.mynginx.com:92;        location / {            root   D:/www/nginx02;            index  index.html index.htm index.php;        }        location ~ \.php$ {            root          D:/www/nginx02;            fastcgi_pass   127.0.0.1:9000;            fastcgi_index  index.php;            fastcgi_param  SCRIPT_FILENAME  $document_root$fastcgi_script_name;            include        fastcgi_params;        }}而后访问http://www.mynginx.com,实际上是轮流访问www.mynginx.com:91,www.mynginx.com:92