On 06/08/2017 09:07 AM, Hendrik Boom wrote:
>
> I have a machine with both old-style MBR (fdisk) partitioned and
> gpt-style (needs gdisk) partitioned disks. It boots using grub or
> lilo.
>

>
> How would booting from the GPT drives work? It's an old machine whose
> BIOS looks for an MBR. I may well be forced to do this is my legacy
> disk drives fail.
>
> If I were to transplant my GPT-formatted drives into a modern machine
> that expects an EFI boot, would it just work? Or would I have to do
> something major -- like repartition -- that puts my data at risk?
>
> -- hendrik
> _______________________________________________


Your old machine may or may not boot from a gpt drive. It is possible to
put an mbr bootloader on a gpt drive. I've done that a couple of times,
and one of the times it (or I) messed things up and had to repartition the
drive.

To boot your gpt drives on uefi hardware, you would need an efi partition
with a bootloader. The efi partition is usually the first partition of the
first hard drive. I haven't tried putting it in a different location. An
easy solution would be to add a hard drive (or even a usb) and install
enough of a system to use it to boot and add your existing system to the
boot menu.

Read this before you play with uefi -
http://www.rodsbooks.com/efi-bootloaders/index.html

fsmithred