Testing for MySQL root password
You can try log into MySQL root as follows
# mysql
If that doesn't work then your root password is not blank. If you think you know the root password try log in as follows.
# mysql -u root -p
Changing MySQL root password
If you cannot get in and you have no way of finding out your current MySQL root password or are not sure where to look you can simply change it.
# service mysqld stop
# mysqld_safe --skip-grant-tables &
You should see mysqld start in safe mode and then get a linux command prompt. If you don't see a command prompt press the ENTER button and you should get it.
# mysql --user=root mysql
> update user set Password=PASSWORD('new-root-password') where user='root';
> \q
# service mysqld restart