Booting Fedora Install from external on Mac

[neiljp85]

I am having trouble booting Fedora from usb attached to my macbook after a successful install.

BLUF: I can install Ubuntu to a flash drive and subsequently boot it on my Macbook fine, but I am not able to do this with Fedora. Why?

More info....

Now I now your going to say "well booting from external memory is not supported by Apples firmware" well the hell with that, I am undeterred. OS X can boot from an external and also I can do it with Ubuntu so what is the difference between Ubuntu and Fedora? Why can one install and boot and the other won't? The Ubuntu and Fedora installers offer some slightly different options regarding bootloader placement. I am going to attempt another install here shortly, I will post a screen shot to illustrate.

Now, booting ubuntu ....took...for....ever.... like 2 mins. But it worked. And once it booted performance was nominal. From refit it would choose grub, from grub choose linux, it would go dark screen for 30 secs, then blinking underscore cursor for 30 secs then scroll text output for 30 secs and then boot. This worked with the volume partitioned with GPT and MBR.

Currently I have refit installed (and blessed) on a 16 mb HFS+ partition on the external drive. Then there is swap space and then the volume that I have as root. These are partitions that I have manualy defined. In the past if I let the installer wipe the drive and use its own partitions and such I would get an error on the install.

It gets more hairy, after a few successful Ubuntu installs and boots (trying different options/configurations) I thought I could finally install Fedora. Even after reformatting the external drive, new partition table and all, in rEFIt it still shows "boot GRUB EFI/ubunutu/grub.efi" The partition labeled EFI *does not exist* and Ubuntu is no longer installed, and rEFIt is running from a previously burned disk. When testing Ubuntu I had created that 'EFI' partition as a 32 MB Fat partition just for the bootloader, but despite it being specified in the Ubuntu install it still put it in /boot/efi after a successful boot, the EFI partition I had made was empty so i got rid of it, and Ubuntu still booted fine.

I think it is a safe assumption my problem is with the bootloader. I don't really know enough to figure this out on my own, I am learning on the fly here. Thanks in advance.

[jayd512]

I am by no means an expert when it comes to Apples... never really messed with them all that much.
But have you tried to boot up with Fedora in your optical drive? Is there an error?
There might just be some proprietary hardware on the computer that might be giving you an issue.

[neiljp85]

Yup, I've never had a problem booting any install disk or Live CD on Apple hardware. I booted Fedora Live CD and did the installation from there no problem. It is getting grub right I think is the issue. Especially since I can take that flash drive with the fresh fedora install and plug it in to another linux box and boot to Fedora just fine.

I also booted earlier with gparted and determined that the EFI/ubuntu/grub.efi that rEFIt was seeing was actually on the 'hidden' EFI partition on my macbook internal drive. Ubuntu put it there. (despite my telling the installer to but the bootloader on the flash drive) I just reformatted that partition to get rid of it (OS X dosnt actually use it ironically)

When installing Ubuntu two installer options show up in the default Apple boot chooser, one says 'Windows' (which is really Ubuntu) and the other says 'EFI Boot' I choose the latter to get the successful install and boot. I went a few steps further with Ubuntu, after running an hour or so of updates it ran update-grub and now i can no longer boot to Ubuntu, I get an error about ELF or something.

I have working on this problem over a week. Sigh.