打开mysql客户端，直接运行以下命令:
1.use mysql;

2.update user set host='%' where user='root';

会报错：ERROR 1062 (23000): Duplicate entry '%-root' for key 'PRIMARY'，直接忽略！

3.flush privileges;

4.grant all privileges on *.* to 'root'@'%' identified by '123456' with grant option;(注：123456换成自定义的登录密码)

5.flush privileges;

重启下mysql服务，ok!