Mysql 拒绝非超级用户访问停靠的MariaDB(超级用户工作)

我使用最新的MariaDB docker映像创建了一个用户xyz，其凭据与根用户的凭据相同:

mysql> SELECT User, Host FROM mysql.user;
+-------------+-----------+
| User        | Host      |
+-------------+-----------+
| root        | %         |
| xyz         | 127.0.0.1 |
| healthcheck | 127.0.0.1 |
| healthcheck | ::1       |
| xyz         | localhost |
| healthcheck | localhost |
| mariadb.sys | localhost |
| root        | localhost |
+-------------+-----------+

和

mysql> show grants for xyz@'127.0.0.1';
+-----------------------------------------------------------------------------------------------------------------------+
| Grants for xyz@127.0.0.1                                                                                            |
+-----------------------------------------------------------------------------------------------------------------------+
| GRANT ALL PRIVILEGES ON *.* TO `xyz`@`127.0.0.1` IDENTIFIED BY PASSWORD '*something'                     |
| GRANT ALL PRIVILEGES ON `somedatabase`.* TO `xyz`@`127.0.0.1`                                                           |
+-----------------------------------------------------------------------------------------------------------------------+

但是，我可以以根用户身份登录，但不能以xyz用户身份登录:

bash> mysql -uroot -h 127.0.0.1 -P3308 -p
Enter password: 
Welcome to the MySQL monitor.  Comm和s end with ; or \g.
Your MySQL connection id is 19
....

bash> mysql -uxyz -h 127.0.0.1 -P3308 -p 
Enter password: 
ERROR 1045 (28000): Access denied for user 'xyz'@'172.17.0.1' (using password: YES)

你知道可能会发生什么事吗？如何调查这一问题？