How to handle hybrid (PC-BIOS + EFI) cloud images

[Thomas Goirand]

On 09/06/2018 08:46 AM, Bastian Blank wrote:
> Moin
> 
> I did some work lately on EFI Debian cloud images.  One type I created
> is a hybrid, aka PC-BIOS + EFI, image.
> 
> This hybrid images will just boot in whatever mode is available.  On IRC
> we came to a bit of an understanding, that this is the way we want to go
> forward.  Microsoft also would like to have this type of images for
> Azure.
> 
> I know that Ubuntu already builds such images.  But I also was told that
> Colin does not like the solution they adopted.
> 
> How could we handle grub installation on such hybrid images?
> 
> In the context of cloud images there are some additional requirements:
> - We may not have EFI nvram, so grub-install call needs at least
>   --no-nvram.
> - The shim needs to be installed as well, when we have some usable.
> - Boot bootloaders variants should always be installed on the disk with
>   the EFI partition on it during upgrades, without question.
> 
> Regards,
> Bastian

And if I may add, in the context of cloud images, we also need:
- Grub must be able to work without a video (ie: some people configure
OpenStack to run without video driver at all in Qemu)
- Grub and the rest of the system must be able to output to serial

Cheers,

Thomas Goirand (zigo)