Change or Set the MySQL Root password
For every database, you should set the root or sa passwords to something other than the default, unless you want to get hacked. For mysql, the system administrator user is called root. You will use the mysqladmin utility from a command line to set the new password. Notice that there are two commands to be run.
Syntax:
mysqladmin -u root password "newpassword"
mysqladmin -u root -h host_name password "newpassword"
Example:
mysqladmin -u root password ws8dr8as3
mysqladmin -u root -h localhost password ws8dr8as3
You will also want to restart the database server after running this command
sudo /etc/init.d/mysql restart


I don't know why, but I needed to use
mysqladmin -u root -p"newpassword" -h host_name password “newpassword”
instead your second command.
After the second command terminal gives that
mysqladmin: connect to server at 'localhost' failed
error: 'Access denied for user 'root'@'localhost' (using password: NO)'
How can I solve that?
Thanks in advance.
Works like a charm on MySQL5. Thanks for the tip.