Grub Problems on Intel Mac Mini

[Ken Mandelberg]

Some time ago I had been booting Ubuntu on a Mac Mini off of the 
internal disk (hd0,2) with refit and legacy grub. At some point this 
broke after some Linux. Mac and hardware changes.

Now I get "GRUB Hard Disk Error", when refit tries to boot off the 
partition. Apparently that means that grub is having trouble with the 
disk geometry it tries to get from the bios when it goes to stage 1.5/2.

I know that the Bios emulation is still there, and Refit thinks the GPT 
and MBR are in sync.

I can boot off a grub cd, which then boots from (hd0,2), but I would 
like to avoid this step.

Any ideas on how to debug this?

---

Another issue is that even with the grub cd there is a limitation. From 
the interactive mode it only sees the internal disk. I have a usb 
external enclosure which grub does not see. Yet if I boot the same cd on 
a notebook, grub does see the same external usb disk. Of course on 
either the mac mini or the notebook, Linux can use the external disk 
once its up.