Re: How to fix Grub if update fails
+1 oldfred. I have cloned and ended up with a duplicate uuid. You end up with a system with split personality and you may never know on which install any changes or updates are made with both in play.
As an alternative I now prefer to simply copy the contents of the clone source to the target source. You do have to to this from a live cd and you have to edit the /etc/fstab file on the target to change the uuid's referenced to those of the target partition(s). You can then update-grub on the source to boot into the target, unplug the source and then install-grub to on the target to make it bootable. It sounds complicate but is actually fast and simple. Best of luck to all for the New Year.
12.10 Quantal w/grub2/Mint13 installed on raid0, Gigabyte AMD MB, AMD 64x4 CPUs at 3.2GHz, 16 GB ram, HD7770 ATI video, dual boot win7 on 64gb ssd and win8 on 1Tb SATA raid. 13.04 installed on raid0 and ssd