- 关闭验证 /etc/my.cnf-->[mysqld]-->skip-grant-tables 
- 重启MySql service mysql restart
- 登陆MySql mysql -u root
- 刷新权限 FLUSH PRIVILEGES;
- 更新密码 ALTER USER 'root'@'localhost' IDENTIFIED BY '123456';
- 退出MySql exit
- 打开验证 /etc/my.cnf-->[mysqld]-->skip-grant-tables 
- 重启MySql service mysql restart
- 登陆MySql mysql -u root -p --> 123456