On 15/01/2023 09:02, Reindl Harald wrote:

Reindl and me wind each other up, so watch out for a flame war :-)

Am 15.01.23 um 09:41 schrieb Wols Lists:

quoted

Are your /boot and /boot/efi using superblock 1.0? My system is 
bios/grub, so not the same, but I use plain partitions here because 
otherwise you're likely to get in a circular dependency - you need efi 
to boot, but the system can't access efi until it's booted ... oops!

the UEFI don't care where the ESP is mounted later
from the viewpoint of the UEFI all paths are /-prefixed

that's only relevant for the OS at the time of kernel-install / updates 
and the ESP is vfat and don't support RAID anyways

But ext4 doesn't support raid either. Btrfs, ZFS and XFS don't support 
md-raid. That's the whole point of having a layered stack, rather than a 
"one size fits all" filesystem.

IF YOU CAN GUARANTEE that /boot/efi is only ever modified inside linux, 
then raid it. Why not? Personally, I'm not sure that guarantee holds.

If you do raid it, then you MUST use the 1.0 superblock, otherwise it 
will be inaccessible outside of linux. Seeing as the system needs it 
before linux boots, that's your classic catch-22.

Basically the rule is, if you want to access raid-ed linux partitions 
outside of linux, you must be able to guarantee they aren't modified 
outside of linux. And you have to use superblock 1.0. If you can't 
guarantee both of those, don't go there ...

Cheers,
Wol