Switch from legacy to UEFI boot??

[Trond Endrestøl]

On Wed, 3 Feb 2016 15:34-0600, Bob Willcox wrote:

> Is there a way to convert a system from legacy boot to UEFI boot?  I have an
> Intel NUC5i7RYH and I can get it to boot ok in legacy boot mode but only if I
> go into the BIOS and manually select the partition. It (the BIOS) won't
> automatically boot from it. Tells me there's no boot device.

UEFI requires the GPT partitioning scheme and a special boot partition 
on the harddrive, a EFI System Partition (ESP).

If you don't have GPT on your drive, your best option is to backup 
anything precious, redo the partitioning, and reinstall your system.

If you already use the GPT partitioning scheme and can make some extra 
room on your harddrive, then you'll be able to create a small ESP of 
800K, and populate that partition with /boot/boot1.efifat.

E.g.:

gpart create -t efi -s 800K -l esp0 ada0
gpart bootcode -p /boot/boot1.efifat -i <index-of-efi> ada0

-- 
+-------------------------------+------------------------------------+
| Vennlig hilsen,               | Best regards,                      |
| Trond Endrestøl,              | Trond Endrestøl,                   |
| IT-ansvarlig,                 | System administrator,              |
| Fagskolen Innlandet,          | Gjøvik Technical College, Norway,  |
| tlf. mob.   952 62 567,       | Cellular...: +47 952 62 567,       |
| sentralbord 61 14 54 00.      | Switchboard: +47 61 14 54 00.      |
+-------------------------------+------------------------------------+