首先跳過權(quán)限認證方式啟動mysql:
修改my.cnf 文件,默認路徑/etc/my.cnf,在[mysqld]模塊下增加skip-grant-tables, 如圖:

1
重啟服務(wù):
service mysqld restart
登錄mysql,刪除mysql.user表中host名為'localhost'的記錄:
[root@localhost ~]# mysql
mysql> use mysql
mysql> delete from user where host='localhost';
Query OK, 7 rows affected (0.00 sec)
mysql> INSERT INTO `user` VALUES ('localhost','root','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','','','','',0,0,0,0,'mysql_native_password','','Y','2021-06-23 03:17:59',NULL,'N');
Query OK, 1 row affected (0.00 sec)
mysql> commit;
Query OK, 0 rows affected (0.00 sec)
修改my.cnf 文件:
刪除[mysqld]模塊下skip-grant-tables
重啟服務(wù):
service mysqld restart
進入MySQL,修改root密碼:
[root@localhost ~]# mysql -uroot
mysql> use mysql
mysql> set password for 'root'@'localhost'=password('newpasswd');