禁止别人直接通过IP访问网站，在nginx的server配置文件前面加上如下的配置，如果有通过IP直接访问的，直接拒绝连接(需要去掉别的server下的default_server)。

server {

    listen   80 default_server;

    listen   [::]:80 default_server;

    server_name  _;

    return 444;

}

如下所示:

# 禁止IP直接访问网站

server {

      listen       80 default_server;

      listen       [::]:80 default_server;

      server_name  _;

      return 444;

}

# zabbix server

server {

         listen  80;

         server_name 123;

         return 301 https://$host$request_uri;

}

server {

         listen  443;

         server_name 123;

         ssl on;

         ssl_certificate       /etc/nginx/cert/zabbix/nginx.crt;

         ssl_certificate_key   /etc/nginx/cert/zabbix/nginx.key;

         ssl_dhparam           /etc/nginx/cert/zabbix/dhparams.pem;

         ssl_protocols TLSv1 TLSv1.1 TLSv1.2;

         ssl_ciphers 'ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:DHE-DSS-AES128-GCM-SHA256:kEDH+AESGCM:ECDHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA:ECDHE-ECDSA-AES128-SHA:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA:ECDHE-ECDSA-AES256-SHA:DHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA:DHE-DSS-AES128-SHA256:DHE-RSA-AES256-SHA256:DHE-DSS-AES256-SHA:DHE-RSA-AES256-SHA:AES128-GCM-SHA256:AES256-GCM-SHA384:AES128-SHA256:AES256-SHA256:AES128-SHA:AES256-SHA:AES:CAMELLIA:DES-CBC3-SHA:!aNULL:!eNULL:!EXPORT:!DES:!RC4:!MD5:!PSK:!aECDH:!EDH-DSS-DES-CBC3-SHA:!EDH-RSA-DES-CBC3-SHA:!KRB5-DES-CBC3-SHA';

         ssl_prefer_server_ciphers on;

         ssl_session_cache shared:SSL:20m;

         ssl_session_timeout 180m;

         location / {

            root /usr/share/zabbix/;

            index index.php index.html;

        }

         location ~ \.php$ {

            root /usr/share/zabbix/;

            fastcgi_pass 127.0.0.1:9000;

            fastcgi_index index.php;

            fastcgi_param SCRIPT_FILENAME /usr/share/zabbix/$fastcgi_script_name;

            include fastcgi_params;

       }

}