How to boot a Linux live USB on a Mac?
Solution 1:
In order to create an Intel Mac bootable USB stick, it needs to be setup for EFI/GPT. This should work as of Fedora 10, but it's not automatic; you need to create a USB stick specifically configured for this purpose.
According to the Fedora 10 release notes, you can do this using the livecd-iso-to-disk
tool like so:
livecd-iso-to-disk --mactel /path/to/live.iso /my/partition
replacing the path and partition as appropriate. However, this post suggests that the MBR may also need to be cleared (destroying all existing data on the USB disk):
livecd-iso-to-disk --mactel --reset-mbr /path/to/live.iso /my/partition
Other details on creating a USB stick are in the Fedora wiki, though curiously nothing about support for Intel Macs. I've had success with this method in the past, though it seems somewhat hit and miss. As far as I know, it's not possible to create a USB stick that will boot on both Intel Macs and non-EFI machines.
Solution 2:
I'm not sure you can do this directly; you might require something like rEFit to be able to boot into an Intel Mac with your live usb.
Have a look at the Myths and Facts About Intel Macs page on their site.
Solution 3:
You may try to press "E" at startup.
Or see if it is visible as a startup disk (System Preferences » Startup Disk) and boot from there (reboot).
Solution 4:
Some notes on booting Intel Mac from external USB drives.
[it is] possible to boot an Intel Mac from a USB flash drive. That is a bit more involved, and there are several methods. One is Das Boot, a free utility from Sub Rosa that allows you to convert original disks from DiskWarrior, Drive Genius, TechTool Pro and others to a flash drive. Let Google be your friend on this. Many people have put their favorite rescue utility on a bootable flash drive to save them from any problems in the field.
Before you ask; no, USB does not support target disk mode -- a sore point for MacBook Air and unibody MacBook owners.