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public text v1 · immutablegrub-install --root-directory=/mnt /dev/sda
Probing devices to guess BIOS drives. This may take a long time.
sed: can't read /mnt/boot/grub/device.map: No such file or directory
grep: /mnt/boot/grub/device.map: No such file or directory
/dev/sda does not have any corresponding BIOS drive.