当一个域名从另一个域名调取文件时出现如下
XMLHttpRequest cannot load http://www.xxx.com/header_data.html. No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://shuju.xxx.com' is therefore not allowed access. The response had HTTP status code 404.
解决办法如下：
location / {
...
add_header Access-Control-Allow-Origin *; #允许所有域名调取，当然这里的'*'号你可以设置指定的域名
...
}