Am 22.02.2023 um 16:30 schrieb Nicolas George: > Is there something I have missed?
I cannot say yes or no. But, of the top of my head, i know, that gdisk does support a strange thing called hybrid between MBR and GPT, where a clean GPT formatted drive contains (instead of a protective MBR) an MBR with pointers to up to four partitons, in order to make a system bootable without UEFI. I understand, that your use case is somewhat different. But maybe you can use the idea anyway. The hybrid formatting has some restrictions, like you should not have standard MBR tools mess this configuration up (not use them at all) and unfortunately that applies to standard GPT tools as well, but the dual bootability can solve some problems. The only issue, i have had a look at, was the problem to have a raid, that is bootable no matter which one of the drives initially fails, a problem, that can be solved by having at least 2 grub installs (on the two mirrors). Certainly, there is a solution to your problem, even if might not exactly fulfill your premises.
