浏览器栏中的域名在加载后更改为IP

Question

我在1und1.de上创建了一个名为medifaktor.de的新域名 然后我添加了数字海洋的名称服务器：

• ns1.digitalocean.com
• ns2.digitalocean.com
• ns3.digitalocean.com

nginx配置文件如下所示：

server {
    listen 80 default_server;
    listen [::]:80 default_server ipv6only=on;

    root /usr/share/nginx/html;
    index index.php index.html index.htm;

    server_name www.medifaktor.de;

    location / {
        try_files $uri $uri/ /index.php?$query_string;
    }

    error_page 404 /index.php;
    error_page 500 502 503 504 /50x.html;
    location = /50x.html {
        root /usr/share/nginx/html;
    }

    location ~ \.php$ {
        fastcgi_split_path_info ^(.+\.php)(/.+)$;
        fastcgi_pass unix:/var/run/php5-fpm.sock;
        fastcgi_index index.php;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
        include fastcgi_params;
        fastcgi_intercept_errors off;
        fastcgi_buffer_size 16k;
        fastcgi_buffers 4 16k;
    }
}

当我现在想要访问它工作的域时，但URL仍然与IP地址交换。我怎么能改变这个？

access.log包含：

185.17.207.244 - - [12/May/2016:13:10:48 +0200] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/50.0.2661.94 Safari/537.36"
185.17.207.244 - - [12/May/2016:13:10:49 +0200] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/50.0.2661.94 Safari/537.36"
74.91.18.46 - - [12/May/2016:13:11:01 +0200] "GET / HTTP/1.1" 200 612 "-" "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0)"