Mon Mar 16 08:08:52 EDT 2015 Gugh. Slept OK, went to bed on time, etc. I'm just in the mood for a slow, lazy morning, and don't have time for one. Goals: Work: - Nail down the final details of EFI boot redundancy We're good with the dd of /boot/efi to /dev/sb1, but... also set bootable with something like: `sudo parted /dev/sdb set 1 boot on` After that, `sudo efibootmgr -v` should show two bootable disks. Hmm. Before I had the chance to try the above, I need to fix what happened Friday. I had unplugged the sda drive to see if it would boot from sdb after I simply dd'd /dev/sda1 to /dev/sdb1. The machine did not boot; it dumped me into the EFI shell. I had assumed that the machine would boot once I plugged sda back in. It doesn't boot. Even with both drives plugged in, it just dumps me to the EFI shell. Why? Why did efi forget about sda1? How do I use EFI shell? https://wiki.archlinux.org/index.php/Unified_Extensible_Firmware_Interface Show current boot entries: Shell> bcfg boot dump -v Hmm. `bcfg` doesn't seem to be available..... efi v1 shells do not support bcfg, only v2 efi. Under efi v1, I did `map` to list the devices. (Actually 'map -b'. Most of the EFI commands, at least in the firmware on this box, seem to take the '-b' flag as a pager.) I could enter a device name, like 'fs1:', to change to that device, like a DOS drive letter. 'dir' and 'cd' took me to a directory at the end of the 'EFI' path, where I ran the grub binary located there. Under linux, we should be able to add efi boot entries like `efibootmgr -c -g -d /dev/sda -p 1 -w -L "Debian" -l /EFI/debian/grubx64.efi`. UPDATE: Much of the above may be done more easily (assuming you have /dev/sda1 and /dev/sdb1 set up as UEFI FAT32 boot partitions) simply with `grub-install /dev/sda1` and `grub-install /dev/sdb1`. `grub-install` should do three things: - generate a grub image (e.g. grubx64.efi) - install the grub image to "/boot/efi/EFI/debian/" - attempt to add an appropriate entry to the UEFI boot menu. Home: - Work on S&W Complete re-typeset Done.