FireWire booting, as the name implies, is the ability to start up a computer from an internal or external FireWire drive.
FireWire booting is possible on all Macintosh models that have built-in FireWire ports with the exception of the Power Macintosh G3 (Blue & White) and the Power Mac G4 (PCI Graphics) models. You may need to upgrade the computer's firmware before FireWire booting will work. You can download the latest firmware for your computer from the Apple Software Updates Web site at http://www.apple.com/swupdates
Do not confuse FireWire booting with FireWire target disk mode as described in this article: "FireWire Target Disk Mode
If you are unsure if your computer has a FireWire port, look for ports that look like those in Figure 1, or look for the FireWire symbol shown in Figure 2.
[img width="68" height="29" src="http://km.support.apple.com/library/APPLE/APPLECARE_ALLGEOS/HT2699/58606_1.gif" alt="" data-hires="true">
Figure 1 FireWire Port
[img width="59" height="56" src="http://km.support.apple.com/library/APPLE/APPLECARE_ALLGEOS/HT2699/58606_2.gif" alt="" data-hires="true">
Figure 2 FireWire Symbol
Follow these steps to start up your computer from an external FireWire drive:
1. Ensure the proper drivers for the FireWire drive are installed in your computer.2. Connect the FireWire drive to your computer and ensure the icon for the disk appears on the Finder desktop.
3. Install the appropriate system software onto the disk.
4. Open the Startup Disk control panel and select the FireWire disk.
5. Restart the computer.The computer should now start up from the FireWire drive. If it does not, make sure you are using third-party drivers that support FireWire booting. Also ensure that the FireWire disk mounts to the Finder desktop and that the system software was properly installed. If it still does not mount, contact the vendor of the device to ensure it can be used as a startup disk.