Binary package hint: grub2
I start my efi-gpt mac mini system using refit.sf.net. I wanted to boot an extern usb-stick using grub2 on there. I had done:
grub-install --recheck --no-floppy --root-directory=/mnt /dev/sdb1
This disk showed up in refit, but it ever failed to boot from there, falling back to my /dev/sda3 ubuntu grub2 without notice.
I had a look in /dev/sda3 ubuntu grub2. It showed all (hd0,x) partitions and one entry was:
"grub> ls"
(fd0)
without any (fd0,1). Trying to "set root=(fd0)" in /mnt/boot/grub/grub.cfg did not succeed. Perhaps I'll try later setting a device.map and without --no-floppy: grub-install --root-directory=/mnt --recheck /dev/sdb1
Browsing through the source http://refit.svn.sourceforge.net/viewvc/refit/ I got the impression there is work underway to utilize some apple firmware bits to get around this well known bug of not getting a second harddisk to boot through refit....
This release of Ubuntu is no longer receiving maintenance updates. If this is still an issue on a maintained version of Ubuntu please let us know.