You can do that from within the RackNerd ctrl panel -> https://ctrl.racknerd.com/
The login details to the ctrl panel was mentioned in your welcome email. If you do not have it, you can view a copy of it here: https://my.racknerd.com/clientarea.php?action=emails
Once logged in, complete the following steps:
1. Click on "Manage" on the VPS you wish to reinstall
2. Click on the "Reinstall" button
3. Select your desired operating system, and then click "Reinstall." Your new root password will be randomly generated and displayed on the top of the page.
