客户端连接MySQL服务器，报错：

解决方案：
没有让root用户远程登录，需要设置；
进入MySQL服务器，修改一下

# mysql -h localhost -uroot -P3306 -p12345678
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 7
Server version: 5.7.42-debug Source distribution

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owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' IDENTIFIED BY '12345678' ;
Query OK, 0 rows affected, 1 warning (5.02 sec)

备注：自己测试用的服务器，密码简单点；