使用nginx做反向代理的时候，可以简单的直接把请求原封不动的转发给下一个服务。设置proxy_pass请求只会替换域名，如果要根据不同的url后缀来访问不同的服务，则需要通过如下方法：

方法1:加"/"

    server {
        listen              8000;
        server_name         abc.com;
        access_log  "pipe:rollback /data/log/nginx/access.log interval=1d baknum=7 maxsize=1G"  main;

        location ^~/user/ {
            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://user/;
        }

        location ^~/order/ {
            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://order/;
        }
    }

^~/user/表示匹配前缀是user的请求，proxy_pass的结尾有/， 则会把/user/*后面的路径直接拼接到后面，即移除user。

方法2：rewrite

    upstream user {
      server localhost:8089 weight=5;
    }
    upstream order {
      server localhost:8090 weight=5;
    }

    server {
        listen              80;
        server_name  abc.com;
        access_log  "pipe:rollback /data/log/nginx/access.log interval=1d baknum=7 maxsize=1G"  main;

        location ^~/user/ {
            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;

            rewrite ^/user/(.*)$ /$1 break;
            proxy_pass http://user;
        }

        location ^~/order/ {
            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;

            rewrite ^/order/(.*)$ /$1 break;
            proxy_pass http://order;
        }
    }

proxy_pass结尾没有/， rewrite重写了url。