Unable to load authentication plugin 'caching_sha2_password'.

问题：caching-sha2-password

处理：

    ALTER USER 'root'@'localhost' IDENTIFIED BY 'password' PASSWORD EXPIRE NEVER; #修改加密规则 
   ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'password'; #更新一下用户的密码 

   FLUSH PRIVILEGES; #刷新权限 

再重置下密码：alter user 'root'@'localhost' identified by '123qwe';