1.vim /etc/my.cnf
[mysqld]
skip-grant-tables ##追加此行，跳过权限表，
2.重启mysql
systemctl restart mysqld
3.mysql 登陆mysql
mysql> use mysql;
mysql> UPDATE user SET Password = password ( 'zha123456' ) WHERE User = 'root' ;
mysql> flush privileges ;
mysql> quit
4.恢复配置文件my.cnf
vim /etc/my.cnf
[mysqld]
skip-grant-tables ##去掉此行，继续校验权限表，
5.重启mysql
systemctl restart mysqld