nacos連接MySQL：Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up.

參考 https://www.cnblogs.com/tingguoguoyo/p/11005584.html
1、進MySQL之后
2、輸入以下語句，進入mysql庫：
use mysql;
3、更新域屬性，'%'表示允許外部訪問：
update user set host='%' where user ='root';
4、執行以上語句之后再執行(刷新配置)：
FLUSH PRIVILEGES;
5、再執行授權語句：
GRANT ALL PRIVILEGES ON . TO 'root'@'%'WITH GRANT OPTION;