求方案 在一个nginx配置中，是否可以用一个域名的不同子目录映射到不同的webman端口

upstream a {
    server 127.0.0.1:6001;
    keepalive 10240;
}
upstream b {
    server 127.0.0.1:6002;
    keepalive 10240;
}

server {
  server_name 站点域名;
  listen 80;
  access_log off;
  root /your/webman/public;

  location ^~ /a {
      proxy_set_header X-Real-IP $remote_addr;
      proxy_set_header Host $host;
      proxy_set_header X-Forwarded-Proto $scheme;
      proxy_http_version 1.1;
      proxy_set_header Connection "";
      if (!-f $request_filename){
          proxy_pass http://a;
      }
  }

  location ^~ /b {
      proxy_set_header X-Real-IP $remote_addr;
      proxy_set_header Host $host;
      proxy_set_header X-Forwarded-Proto $scheme;
      proxy_http_version 1.1;
      proxy_set_header Connection "";
      if (!-f $request_filename){
          proxy_pass http://b;
      }
  }

}