I have been trying and failing to boot any OS from an external USB HDD on my MacBook Pro Core 2 Duo and have been seeking help in the Ubuntu forums (see http://ubuntuforums.org/showthread.php?t=510030 - I'm lotus49 BTW).

Cyberdork33 pointed me in the direction of this list and quoted the following that was posted recently:

Last weekend I installed Ubuntu 7.10 on an external harddrive attached
to my MacBookPro via USB.

- First installed rEFIt.
- Then installed Ubuntu to the external drive WITHOUT installing grub.
- Note the device name, /dev/sdb in may case.
- Then installed grub manually, using the device name from above.

After that the Ubuntu installation shows up as a boot option in rEFIt.

Hope this helps,
Zoltan


I would love to know exactly what sort of a MBP this was.  If you read through the (rather long) thread you will see that I have referred to other posts on various blogs/forums where people have stated that they have also been successful booting either XP or Ubuntu from a USB HDD on either a MacBook or a MacBook Pro Core Duo, but so far I have not found any evidence that anyone has managed this on a MBP C2D.

Zoltan, if you are reading this, can you let me know exactly which MBP you have and if it's the C2D version, what firmware version are you running?

TIA,
lotus49