reset mysql root password — сбросить пароль пользователя root mysql
service mysqld stop
mysqld_safe --skip-grant-tables &
mysql -uroot
use mysql; update user set password=PASSWORD("NewPassword") where User='root'; flush privileges; quit
service mysqld restart
По теме:
https://support.rackspace.com/how-to/installing-mysql-server-on-centos/
https://support.rackspace.com/how-to/mysql-resetting-a-lost-mysql-root-password/