nginx配置文件中加入以下代码：

    listen         80 default_server;
    listen         [::]:80 default_server;
    listen 443 ssl default_server;
    listen [::]:443 ssl default_server;
    server_name _;
    set $empty "";
    ssl_ciphers aNULL;
    ssl_certificate data:$empty;
    ssl_certificate_key data:$empty;
    return 444;

注释掉之前默认配置即可。