On Fri, Jan 11, 2019 at 04:56:07PM -0800, Patrick Bartek wrote:
On Fri, 11 Jan 2019 07:13:30 -0500 Michael Stone <mstone@debian.org> wrote:On Thu, Jan 10, 2019 at 03:53:11PM -0800, Patrick Bartek wrote: >Plus, I >want to have a common-shared /boot partition for possible future >upgrades or expansions. This is a really bad idea, and will cause far more trouble than it can possibly save in the future. You do need one EFI partition per system, and you can have different directories there for different OSs.You misunderstood as I was too general in my post about partitioning. I WILL have a dedicated EFI System Partition (ESP) formatted FAT32 marked with the "boot" flag AS WELL AS a dedicated partition with a mount point of /boot /boot/efi will be the mount point for the ESP. As far as I've read UEFI booting firmware, etc. does not require this. It's a Linux recommendation. But I could be wrong: UEFI/GPT is new to me.
I'm not really sure what you're trying to say here. Yes, the UEFI spec doesn't talk about where to put the efi partition in a linux system, because it isn't a linux spec. In theory you can put it anywhere or nowhere (it's not used in day-to-day operation at all). But, if you intend to put grub on it using the normal install process, it needs to be in /boot/efi or the install won't work. (By default it will be in /boot/efi/EFI/debian.) It is possible to manually put it somewhere else, or to use a directory other than debian. I'm not sure why you would decide to mount it elsewhere, as I can't see any benefit to doing so. Putting grub in a directory other than "EFI/debian" does allow for multiple OSs to have their own boot loaders which can be started from the UEFI boot menu. (E.g., you could have EFI/stretch, EFI/centos7, EFI/sid, etc.) In this case I would still keep the efi partition mounted on /boot/efi to reduce long-term confusion. I'd also add new directories instead of trying to keep multiple versions of debian from overwriting the debian directory.
In addition to the efi partition, where the boot loader goes, you also need a /boot partition where the kernel and the grub menu configuration go. (Actually, in most cases this does not need to be a separate partition, but you do need a /boot directory.) You talk about sharing the /boot partition and this is what I said was a really bad idea: have a separate /boot per install or you'll have multiple installs stomping on each other's boot configs.
Just about everything above can in theory be worked around or done differently, but you'll be way outside of what you can expect support for at that point.