I think I've done everything reasonable in my firmware to ensure booting by EFI. I have:
Storage boot option control UEFI only Other PCI device ROM priority UEFI only (other options for both are "Legacy only" and "Disabled") The boot device is currently /dev/sdb which has a GPT partition table, and its first few partitions are number size mount point 1 953MB /boot 2 2GB / 3 10GB /usr 11 9GB /home 13 48GB swap 5 953MB unmounted, filesystem="grub2 core.img", flags="bios_grub" The first four are ext4. I do recall it was a pain to make d-i keep the GPT table not overwrite it with an MBR one. My motherboard is a Gigabyte H170 with 32 GiB RAM and I run Debian 12.8. I swear I ran a program that showed me EFI boot vars (if they exist) and it showed nothing. But now I can't remember what that program was. How can I ensure that I'm actually booted using EFI?
