How to reset root password in Oracle Redhat

e.g., ....rhgb quiet single
 * Press e key while rebooting
 * Select Oracle Linux Server Unbreakable Enterprise Kernel .... (Don't press Enter.)
 * Press e to edit.
 * Select kernel /vmliuz-.....
 * Press e to edit.
 * Append single to the original syntax and then press Enter.
 * Press b to boot
 * System will boot up in the single mode.
 * At # prompt, type passwd to change the root password.
 * Type reboot to reboot.