Ok, so I confirm that this is definitely a bug. Since MAAS doesn't write UEFI config onto the fs, I believe this is a curtin issue. What I've done to reproduce is to install 3 different machines:
A. Machine on legacy boot mode
B. Machine on EFI mode (NUC)
C. Machine on EFI mode (Server)
I then did;
1. killed MAAS completely.
2. rebooted (A), the machine booted into the OS just fine.
3. rebooted (B), the machine didn't boot into the OS.
4. rebooted (C), the machine didn't boot into the OS.
Ok, so I confirm that this is definitely a bug. Since MAAS doesn't write UEFI config onto the fs, I believe this is a curtin issue. What I've done to reproduce is to install 3 different machines:
A. Machine on legacy boot mode
B. Machine on EFI mode (NUC)
C. Machine on EFI mode (Server)
I then did;
1. killed MAAS completely.
2. rebooted (A), the machine booted into the OS just fine.
3. rebooted (B), the machine didn't boot into the OS.
4. rebooted (C), the machine didn't boot into the OS.