User Guide

36 Chapter 3 Protecting Hardware and Securing Global System Settings
To secure startup, perform one of the following tasks:
 Use the Open Firmware Password application to set the Open Firmware password
 Set the Open Firmware password within Open Firmware
 Verify and set the security mode from the command line
Open Firmware password protection can be bypassed if the user changes the
physical memory configuration of the machine and then resets the PRAM three times
(by holding down Command, Option, P, and R keys during system startup). An Open
Firmware password will provide some protection, however, it can be reset if a user has
physical access to the machine and can change the physical memory configuration of
the machine.
You can require a password to start single-user mode, which would further secure your
computer.
For more information about Open Firmware password protection, see AppleCare
Knowledge Base article #106482, “Setting up Open Firmware Password protection in
Mac OS X 10.1 or later” (www.apple.com/support/), and AppleCare Knowledge Base
article #107666, “Open Firmware: Password Not Recognized when it Contains the Letter
‘U’” (www.apple.com/support/).
Using the Open Firmware Password Application
The Mac OS X installation disc includes Open Firmware Password application,
an application that allows you to enable an Open Firmware or EFI password.
To use the Open Firmware Password application:
1 Log in with an administrator account and open Open Firmware Password application
(located on the Mac OS X installation disc in /Applications/Utilities/).
2 Click Change.
3 Select “Require password to change Open Firmware settings.”
To disable the Open Firmware or EFI password, deselect “Require password to change
Open Firmware settings.” You won’t have to enter a password and verify it. Disabling
the Open Firmware password is only recommended for when you install Mac OS X.
4 Enter a new Open Firmware or EFI password in the Password and Verify fields. Click OK.
This password can be up to eight characters.
Do not use the capital letter “U” in an Open Firmware password.
WARNING: Open Firmware settings are critical. Take great care when modifying these
settings and when creating a secure Open Firmware password.