Re: Obtaining the UUID of the system for a PXE boot

[Andrey Borzenkov]

On Wed, Jul 17, 2013 at 3:19 PM, Holger Goetz <address@hidden> wrote:
> Hello all,
>
> i've started to use grub.efi as boot loader for UEFI based systems and am
> getting slowly familiar w/ grub2.Now i've come across a problem w/ assigning
> individual boot configurations to target system identification.
> The BIOS line of systems gets booted through pxelinux and get their PXE
> configuration through files w/ names based on the individual UUID of the
> system.
> The same should be possible for UEFI booted systems, but i couldn't find a
> way to get hold of the system-UUID yet. The MAC addresse(s) is/are not
> available and possibly have changed since the definition of the
> configuration, so even the lately introduced net_default_mac variable
> doesn't work here. Having the UUID as unique system identifyer across NICs
> which can be changed would be of big help.
>
> Any pointer/help would be greatly appreciated.
>

So, you need to fetch system GUID used by PXE, right? To be honest, I
do not even know how (if it is possible at all) to obtain it. The only
words about PXE GUID in EFI allow to switch between using GUID and MAC
for client identification, but that's all:

===
SendGUIDThis field is used to change the Client Hardware Address
(chaddr) field in the DHCP and Discovery packets. Set to TRUE to send
the SystemGuid (if one is available).
===

Do you know how to get this information?