分类：Linux

·MySQL8.0登录连接报错caching_sha2_password

#2054 - The server requested authentication method unknown to the client
mysqli_real_connect(): The server requested authentication method unknown to the client [caching_sha2_password]
mysqli_real_connect(): (HY000/2054): The server requested authentication method unknown to the client

·用docker构建mysql容器后连接报错caching_sha2_password

Authentication plugin 'caching_sha2_password' cannot be loaded: dlopen(/usr/local/mysql/lib/plugin/caching_sha2_password.so, 2): image not found
mysqli_real_connect(): The server requested authentication method unknown to the client [caching_sha2_password]
mysqli_real_connect(): (HY000/2054): The server requested authentication method unknown to the client

一、已安装好的数据库

1.登录数据库

mysql -uroot -p

2.查看身份验证类型

mysql> use mysql;
Database changed

mysql> SELECT Host, User, plugin from user;
+-----------+------------------+-----------------------+
| Host      | User             | plugin                |
+-----------+------------------+-----------------------+
| %         | root             | caching_sha2_password |
| localhost | mysql.infoschema | caching_sha2_password |
| localhost | mysql.session    | caching_sha2_password |
| localhost | mysql.sys        | caching_sha2_password |
| localhost | root             | caching_sha2_password |
+-----------+------------------+-----------------------+
5 rows in set (0.00 sec)

root 用户的验证器插件为 caching_sha2_password

3.修改身份验证类型(修改密码)

mysql> ALTER USER 'root'@'%' IDENTIFIED WITH mysql_native_password BY '123456';
Query OK, 0 rows affected (0.00 sec)

mysql> ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY '123456';
Query OK, 0 rows affected (0.01 sec)

mysql> FLUSH PRIVILEGES;

4.验证是否生效

mysql> use mysql;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
mysql> SELECT Host, User, plugin from user;
+-----------+------------------+-----------------------+
| Host      | User             | plugin                |
+-----------+------------------+-----------------------+
| %         | root             | mysql_native_password |
| localhost | mysql.infoschema | caching_sha2_password |
| localhost | mysql.session    | caching_sha2_password |
| localhost | mysql.sys        | caching_sha2_password |
| localhost | root             | mysql_native_password |
+-----------+------------------+-----------------------+
5 rows in set (0.00 sec)

root用户的身份验证器插件已经变为mysql_native_password

二、第一次安装mysql或构建容器、新增用户

1.配置 mysql.cnf 配置默认身份验证插件（对于构建容器可以采用*2的办法）

[mysqld]
default_authentication_plugin = mysql_native_password

*2.构建容器的时候，指定身份验证插件

command: --default-authentication-plugin=mysql_native_password