I have a few questions relating to the EFI Firmware utility thats hidden but supplied on the Snow Leopard install disc. Essentially I’ve installed this and set a password on my mac, the effect of that is holding down the C key on boot up prevents you from booting off a CD to reformat the hard drive if the mac were to be stolen for example. However what I dont understand is
1. If I want to now boot off a CD, how can I do this in the future if holding down C is disabled.
2. If I have to disable the password by loading up OSX and rerunning the Firmware utility, what would I do in the event my mac installation becomes corrupt and wont boot up, is my mac then a brick ?
3. Would you recommend using this utility. The reason I’m using it, is that as part of some anti theft software I’m using (Undercover) it recommends setting this password and having it in place.
—–
Scott Fairclough
The only way to boot from a CD, I'm pretty sure, would be to turn this feature off first. You may also be able to use the Startup Disk System Preferences panel to do it, entering your password first, but I'm not sure on that.
If your Mac becomes corrupt or something goes wrong, I assume that you've lost all data. You can probably get the drive out of the machine and wipe it and start from scratch. Not completely sure on that either, as I've never had to do it, of course.
I don't recommend using this unless you them physical security a big threat to you and you have sensitive information on your Mac. In other words, what would be a bigger disaster to you: someone stealing your Mac and getting all of your data on it, or losing the data because of a problem arising from using this technique. And which is more likely to happen?
There are other ways of protecting your data that aren't as extreme. Like using 1Password for passwords.
Even Apple doesn't recommend using this. See: http://support.apple.com/kb/ht1352
I had to take my MacBook to the Genius Bar recently to get the battery replaced. The Genius bar tech needed to 'netboot' my MacBook to run their hardware diagnostic, but couldn't because I had a firmware password; I was about to offer to disable it for him but instead he whisked it to the back room, and came back. He said all you have to do to bypass the firmware password is remove and re-seat one stick of RAM. Apparently any change in the hardware configuration disables the firmware password. I'm guessing you have to power the machine up at least momentarily with the 'different' configuration before putting things back where they were.
If you hold down option key, you can choose the SuperDrive with SL disk in it, and can boot from there.