> I confirm that gdisk can convert a disk from MBR/MSDOS to GPT from > within a system running on the disk.
Indeed that's exactly what I used for that. > Anyway, unless the UEFI firmware is broken, you can boot in UEFI mode > from an MSDOS partitionned disk, provided that you can create a small > FAT32 EFI system partition (a few MB IIRC). Good to know, thanks. >> You may need extra steps to convince your system to boot from Debian's >> grub-efi, > Not "may", "must". > Unless the system was booted in UEFI mode, the default GRUB EFI > installation process will fail. [...] > IMO a more elegant way is to install GRUB with the following options : > grub-install --target=x86_64-efi --removable > (or --target=i386-efi depending on the firmware flavour) > It does not require access to any EFI boot variable and will install > GRUB in the default EFI path. Ah, yes, that rings a bell. Indeed, I had some difficulty convincing GRUB to install itself (I seem to remember that it had trouble deciding which target to use, at least). I should have written down the steps I followed back then. Stefan