Bug#1032435: installation-reports: Fails to install GRUB bootloader

[John Talbut <jt@dpets.uk>]

Thanks, Pascal, you gave me some more ideas where to look.

I have spent a lot of time on this without being able to discover 
exactly where the error lay in order to be able to correct it without 
going back to square 1.  In the end the only thing that has worked has 
been a complete reinstall including erasing all previous information in 
all partitions.

Consistently what was happening whatever I did was that when I tried to 
boot it would go straight to grub>: - The grub prompt on a blank screen. 
 When I checked the settings and files information on this screen, e.g. 
using ls and set commands, the information never corresponded to what 
was actually installed.

Clearly something was wrong that was used very early in the boot process 
but I was unable to find what.  None of the information that I could 
find online that I could make sense of stated exactly which files or 
settings the UEFI firmware first goes to.

One thing that seems to be the case but is not made clear is that grub 
needs two partitions for booting.  One is a plain EFI partition and the 
other is a normally formatted (e.g. ext4) partition mounted at /boot. 
Confusingly, although the EFI partition seems to get mounted as 
/boot/efi it has to be a separate partition in the installer 
partitioning scheme.