Startup Keys available with EFI Password set

[Jason]

I've enabled an EFI firmware password on a test system (never used it before). My initial thought was that all Startup key combinations would still work, I'd just be prompted for the firmware password but that doesn't seem to be true. So far only Command-R and Option keystrokes work. Is this expected behavior? Apples documentation doesn't differentiate between key combinations that work with or without a firmware password set.

http://support.apple.com/en-us/HT201255

Just trying to understand which options should work before deciding to enable it or not.

[davidacland · Accepted solution]

Not a definitive answer but we normally use it with the alt (option) key only so we can access netboot (or other disks). From memory I think the intention is to disable most of the other modifier keys (N, T etc). I think single user mode and verbose mode are also locked out.

[davidacland · Accepted solution]

Not a definitive answer but we normally use it with the alt (option) key only so we can access netboot (or other disks). From memory I think the intention is to disable most of the other modifier keys (N, T etc). I think single user mode and verbose mode are also locked out.

[mm2270 · Accepted solution]

Yes, only Option and Command R actually respond with a prompt for the password while the EFI Firmware password is in place. Single User Mode, Verbose and a few other key combos do not work until the password is removed. Its a little bit of a pain, but that's how it works.

[Jason]

Thanks @davidacland and @mm2270