[syslinux] syslinux.efi and vendor-class-identifier

[Gene Cumm]

On Fri, Oct 11, 2019 at 10:27 AM James Pearson via Syslinux
<syslinux at syslinux.org> wrote:
>
> James Pearson via Syslinux wrote:
> >
> > However, I have just tested the exact same boot procedure using a Dell
> > laptop (Latitude 7480) - and it all worked without a problem - that is,
> > syslinux.efi and ldlinux.e64 were downloaded without a problem - and
> > from a tcpdump, there was *no* DHCP transaction between downloading
> > syslinux.efi and ldlinux.e64
> >
> > So I'm puzzled as to why it doesn't work on the Dell 3930 - may be a
> > firmware bug/feature (it is running the latest firmware) ?
>
> Also tested with an HP laptop (Zbook 15u G5) and this shows the _exact_
> same issue as with the Dell 3930 ... so the issue is looking more and
> more like a problem somewhere with syslinux.efi ?

It's a client-specific interaction that I haven't seen.  My guess is
the attempts to just use the default address works better on some
clients but triggers this second DHCP cycle on other clients.

I'm assuming whatever versions you're using are the precompiled
binaries from the source/binary tarballs from kernel.org?

In the packet captures, I'm guessing the UEFI firmware did DHCP, fetch
syslinux.efi then very quickly thereafter started the broken DHCP
cycle?

-- 
-Gene