vim /etc/my.cnf文件；
在[mysqld]后添加skip-grant-tables（登录时跳过权限检查）

重启MySQL服务：sudo systemctl restart mysqld

登录mysql，输入mysql –uroot –p；直接回车（Enter）

输入：set password for 'root'@'localhost'=password('admin');

如果报：ERROR 1290 (HY000): The MySQL server is running with the --skip-grant-tables option so it cannot execute this statement

输入：flush privileges;

再次输入：set password for ‘root’@‘localhost’=password(‘Admin123@qwe’);

为避免麻烦，再次设置远程访问

GRANT ALL PRIVILEGES ON *.* TO 'root'@'%'IDENTIFIED BY 'Admin123@qwe' WITH GRANT OPTION;

flush privileges;

退出：exit

再把my.ini的skip-grant-tables删除或者注释掉

重启MySQL：sudo systemctl restart mysqld