现在一台服务器上跑了gm,web,qh,mb 4个网站，最开始只有gm，web，qh 3个。今天我加了mb之后，发现访问mb的时候，有一定几率跳到web上，不知道什么原因。 下面上配置：

    upstream nodejs__upstream_gm {
		server 127.0.0.1:8001 weight=1;
	}
	upstream nodejs__upstream_web {
		server 127.0.0.1:8002 weight=1;
	}
	upstream nodejs__upstream_qh {
		server 127.0.0.1:1337;      	
	}		
	upstream nodejs__upstream_mb {
		server 127.0.0.1:3000;      	
	}	
    server {
        listen       80;
        server_name  www.域名.com;
        location / {
            root   html;               
            index  index.html index.htm;                
			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-Nginx-Proxy true;
            proxy_pass   http://nodejs__upstream_web;
        }
        #error_page  404              /404.html;
        # redirect server error pages to the static page /50x.html
        #
        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
            root   html;
        }
    }	

    server {
        listen 80;      
		server_name gm.域名.com;			
        location / {
            root   html;
            index  index.html index.htm;
			proxy_pass   http://nodejs__upstream_gm;            
            client_max_body_size 10m;      
            client_body_buffer_size 128k;   
        }		
		# redirect server error pages to the static page /50x.html
        #
        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
            root   html;
        }
    }	
	
	server {
        listen       80;
        server_name 	qh.域名.com;		
        location / {
            root   html;
            index  index.html index.htm;
            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-Nginx-Proxy true;
			proxy_pass   http://nodejs__upstream_qh;			
			proxy_read_timeout 10;
        }				
		# redirect server error pages to the static page /50x.html
        #
        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
            root   html;
        }
    }	
	
	server {
       listen 80;
        server_name mb.域名.com;		
		location / {
			root   html;
            index  index.html index.htm;
            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-Nginx-Proxy true;
			proxy_pass   http://nodejs__upstream_mb;		
			proxy_read_timeout 10;		
		}				
		# redirect server error pages to the static page /50x.html
        #
        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
            root   html;
        }
    }