On Fri, May 6, 2016 at 8:47 AM Stefan Monnier <monn...@iro.umontreal.ca> wrote:
> > 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. > > However in this case the disk was GPT partitioned from the start, although not initially in a UEFI compatible way (no ESP, as I didn't know it was required at first). The non-UEFI boot was from a USB stick. > > 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). > > That's interesting, and may be the explanation for the problem I encountered in 11) below (which didn't stop me but puzzled me for a minute). In the end I got it to work by doing the following, after building the full system on the /dev/sda and finding it wouldn't boot, and fixing the partition scheme and still not being able to boot: 1) Buy two new USB sticks from the local store, one small ,one larger. 2) Download Jessie netinst from ftp.jaist.ac.jp (I'm in Japan), burn to smaller USB stick 3) Boot from smaller USB stick with larger USB stick connected, install Jessie minimal install (no DE) to larger USB stick without mounting or touching the system's SSD. Verify on grub menu as install was about to start that was in UEFI mode. 4) Back to the store for a wired USB keyboard as the installer doesn't support bluetooth even though the live does, at least not in the early stages. Finish install. 5) Boot into new Jessie on larger USB stick. Verify EFI mode. (/sys/firmware/efi/efivars exists) 6) Mount root partition of target install on the machine's SSD (/dev/sda2 -- /dev/sda1 being the ESP) at /mnt/lfs 7) Do the dance of several mounts eg bind mount /dev, remount devpts, proc, sysfs and tmpfs, then chroot into the LFS environment. Mount the ESP at /boot/efi . 8) efibootmgr with no params now runs without errors and lists up existing boot settings -- THIS IS THE BREAKTHROUGH. At this point, Debian-installed kernel is running, but all tools, libraries etc are self-built as per LFS since I'm in the chroot. 9) Run grub-install again -- no complaints this time about EFI variables. 10) Reboot -- grub runs but fails to boot new kernel. 11) Try to boot USB-installed Jessie again -- machine now refuses to boot it. Dunno why probably something to do with the grub-install I did for LFS. 12) Boot original Debian Live USB stick again, which works. Mount /dev/sda2 and fix the grub.cfg file from all the mess I made earlier while trying to get it to work. Also fix a bug in the file introduced from the original instructions I was following which had a very small but important error -- a semicolon in the boot instructions before the root= option... 13) Reboot and watch the LFS instance boot successfully! Thanks to all who helped. Hopefully these steps will attract critique and/or help others who follow on the same path. Overall I have some impression that the people making the live ISOs and the people making the installer are not talking to each other as much as they COULD be. eg live supports bluetooth successfully, installer doesn't, installer supports UEFI boot, live doesn't, etc. One of the few significant downsides to community-based projects I suppose -- the upsides obviously dwarf such downsides. Overall Debian rocks! Mark
