Re: GRUB2 PXE chainloading and EFI handles

[Randy Goldenberg]

My understanding is that your boot process requires two network boots, and
the second one fails.

I don't know what's involved in "looking up some EFI handles", but if the
reason for the failure is that necessary files are not available to the
loader, wimboot may help.

https://ipxe.org/wimboot

Although wimboot was created to enable network boot into Windows, it can be
used as general utility for loading files into what amounts to a ramdisk.

If the reason for the failure is that there is no longer an  EFI
application capable of netboot in memory, iPXE may help.

https://ipxe.org/

https://ipxe.org/cmd/chain



On Sun, Apr 14, 2024 at 6:07 AM kitzman <kitzman@disroot.org> wrote:

> Dear all,
>
> I'm here to ask for some help - I'm not an EFI expert so brace
> yourselves.
>
> I have the following situation: I PXE boot EFI GRUB2, which has menu
> entries for some operating systems.
> One of the operating systems requires chainloading - only the loaded
> bootloader knows how to load the kernel
> and the configuration (9front).
>
> My problem is that: once GRUB2 chainloads, and the second bootloader is
> running, some EFI handles
> are not there. The second bootloader, on startup, checks if it
> should/can PXE, ISO or local disk boot.
> The PXE check is done by looking up some EFI handles for the PXE
> protocol, and such handles also allow
> it to use the network - but they are not found, and it falls back to
> local disk boot.
>
> Is there a way to leave the handles there? Maybe it's not GRUB2 deciding
> if those handles
> should be there anymore? Maybe I'm assuming that's the problem? I don't
> know.
>
> Kind regards,
> kitzman
>
>