https://johnlewis.ie/booting-linux-under-uefi-and-legacy-bios/
https://www.mankier.com/8/grub2-switch-to-blscfg#--config-file
https://aws.amazon.com/cn/premiumsupport/knowledge-center/ec2-linux-recover-blscfg-file/
https://askubuntu.com/questions/399732/how-to-check-if-grub-is-in-efi-or-bios-mode
https://access.redhat.com/solutions/3236591
The GPT specification requires that the alternate GPT is at the end of the disk.
https://access.redhat.com/solutions/3057011
https://access.redhat.com/solutions/114503
https://access.redhat.com/solutions/4311021
https://www.rodsbooks.com/gdisk/repairing.html
https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/6/html/virtualization_administration_guide/sect-qemu_guest_agent-running_the_qemu_guest_agent_on_a_windows_guest
https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/6/html/deployment_guide/sec-emergency_mode