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Tom Yan
Tom Yan
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Well it sounds like when you install Ubuntu, the installer / you chose to use the EFI system partition (ESP) on the internal drive instead of creating its own on the external one.

The solution can be somewhat distro-specific, but obviously the idea is to prevent the former / current case from happening. If the installer is too "streamlined" / "user-friendly" to allow you to customize whether it should use any existing ESP found on the system, another way would be to disable / disconnect the internal drive temporarily.

Also note that some UEFI firmware might purge boot entry that looks for file that no longer exists, so it's preferredit might be preferable to use the fallback path (i.e. /EFI/Boot/bootx64.efi / --removable of grub-install) in such case instead of nvram registration.

(It's also UEFI-specific though. IIRC for AMI Aptio, it may not provide boot order setting that comes with an "abstract" boot entry item of "USB drive". In that case NVRAM registration might be instead the way to go, otherwise your "if plugged boot that" plan may not work because the boot order is not "fixed".)

It may not be necessary to re-install the whole system, when e.g. you can allocate some space for a new ESP on the drive (it does not have to be at the beginning of the drive). You can then fix the mountpoint, remove the old boot entry with efibootmgr, and re-install grub, all done in the normal environment after bootbooting the installation. (And optionally clean up the grub files on Windows / internal drive ESP.)

Well it sounds like when you install Ubuntu, the installer / you chose to use the EFI system partition (ESP) on the internal drive instead of creating its own on the external one.

The solution can be somewhat distro-specific, but obviously the idea is to prevent the former / current case from happening. If the installer is too "streamlined" / "user-friendly" to allow you to customize whether it should use any existing ESP found on the system, another way would be to disable / disconnect the internal drive temporarily.

Also note that some UEFI firmware might purge boot entry that looks for file that no longer exists, so it's preferred to use the fallback path (i.e. /EFI/Boot/bootx64.efi / --removable of grub-install) in such case instead of nvram registration.

It may not be necessary to re-install the whole system, when e.g. you can allocate some space for a new ESP on the drive (it does not have to be at the beginning of the drive). You can then fix the mountpoint, remove the old boot entry with efibootmgr, and re-install grub after boot. (And optionally clean up the grub files on Windows / internal drive ESP.)

Well it sounds like when you install Ubuntu, the installer / you chose to use the EFI system partition (ESP) on the internal drive instead of creating its own on the external one.

The solution can be somewhat distro-specific, but obviously the idea is to prevent the former / current case from happening. If the installer is too "streamlined" / "user-friendly" to allow you to customize whether it should use any existing ESP found on the system, another way would be to disable / disconnect the internal drive temporarily.

Also note that some UEFI firmware might purge boot entry that looks for file that no longer exists, so it might be preferable to use the fallback path (i.e. /EFI/Boot/bootx64.efi / --removable of grub-install) in such case instead of nvram registration.

(It's also UEFI-specific though. IIRC for AMI Aptio, it may not provide boot order setting that comes with an "abstract" boot entry item of "USB drive". In that case NVRAM registration might be instead the way to go, otherwise your "if plugged boot that" plan may not work because the boot order is not "fixed".)

It may not be necessary to re-install the whole system, when e.g. you can allocate some space for a new ESP on the drive (it does not have to be at the beginning of the drive). You can then fix the mountpoint, remove the old boot entry with efibootmgr, and re-install grub, all done in the normal environment after booting the installation. (And optionally clean up the grub files on Windows / internal drive ESP.)

Source Link
Tom Yan
Tom Yan
  • 10k
  • 2
  • 18
  • 37

Well it sounds like when you install Ubuntu, the installer / you chose to use the EFI system partition (ESP) on the internal drive instead of creating its own on the external one.

The solution can be somewhat distro-specific, but obviously the idea is to prevent the former / current case from happening. If the installer is too "streamlined" / "user-friendly" to allow you to customize whether it should use any existing ESP found on the system, another way would be to disable / disconnect the internal drive temporarily.

Also note that some UEFI firmware might purge boot entry that looks for file that no longer exists, so it's preferred to use the fallback path (i.e. /EFI/Boot/bootx64.efi / --removable of grub-install) in such case instead of nvram registration.

It may not be necessary to re-install the whole system, when e.g. you can allocate some space for a new ESP on the drive (it does not have to be at the beginning of the drive). You can then fix the mountpoint, remove the old boot entry with efibootmgr, and re-install grub after boot. (And optionally clean up the grub files on Windows / internal drive ESP.)