How to reset mysql root password

Start server
$ sudo service mysql start

Go to sock folder
$ cd /var/run

Back up the sock
$ sudo cp -rp ./mysqld ./mysqld.bak

Stop server
$ sudo service mysql stop

Restore the sock
$ sudo mv ./mysqld.bak ./mysqld

Start mysqld_safe
$ sudo mysqld_safe --skip-grant-tables --skip-networking &

Init mysql shell
mysql -u root

Change password
FLUSH PRIVILEGES;
SET PASSWORD FOR root@'localhost' = PASSWORD('my_new_password');