Reset MySQL password

The Server root user is the server's main user. The MySQL root user has complete control over MySQL only. The two 'root' users are not connected in any way.

Stop MySQL

The first thing to do is stop MySQL. If you are using Ubuntu or Debian the command is as follows:

sudo /etc/init.d/mysql stop

For CentOS, Fedora, and RHEL the command is:

sudo /etc/init.d/mysqld stop

Safe mode

Next we need to start MySQL in safe mode - that is to say, we will start MySQL but skip the user privileges table. Again, note that you will need to have sudo access for these commands so you don't need to worry about any user being able to reset the MySQL root password:

sudo mysqld_safe --skip-grant-tables &

Note: The ampersand (&) at the end of the command is required.

Login

All we need to do now is to log into MySQL and set the password.

mysql -u root

Note: No password is required at this stage as when we started MySQL we skipped the user privileges table.
Next, instruct MySQL which database to use:

use mysql;

Reset Password

Enter the new password for the root user as follows:

update user set password=PASSWORD("mynewpassword") where User='root';

and finally, flush the privileges:

flush privileges;

Restart

Now the password has been reset, we need to restart MySQL by logging out:

quit

and simply stopping and starting MySQL.

On Ubuntu and Debian:

sudo /etc/init.d/mysql stop
...
sudo /etc/init.d/mysql start

On CentOS and Fedora and RHEL:

sudo /etc/init.d/mysqld stop
...
sudo /etc/init.d/mysql start

Login

Test the new password by logging in:

mysql -u root -p

You will be prompted for your new password.