I'm on Ubuntu 11.10 64bit booting using rEFIt on a 8,3 2011 Macbook Pro.
I recently switched out the hard drive and modified the order of the partitions when duplicating the disk. Everything's working fine, it's just that I get a "Missing operating system" message when trying to boot into Linux. I'm assuming that the problem is that what was once root at
/dev/sda5 is now something else.
How can I update GRUB2 to point to the right partitions for my root directory and swap? I know which partitions are which, I just need to reconfigure things. (GRUB is installed at
/dev/sda, to allow rEFIt to work.) I already tried using Boot-Repair, but it didn't fix things as it still won't boot. I'm currently running from a LiveCD and I've mounted the drive, looking for the right configuration file.
What do I need to change and where?