[Dnsmasq-discuss] [PATCH] Re: pxe-service entries in dnsmasq conf seem to fail non-proxy EFI boot

Shrenik Bhura shrenik.bhura at gmail.com
Sat Oct 9 09:48:20 UTC 2021


Hey Petr,

I have read your post a few times but am only partially able to understand
everything. It may be my lack of knowledge of the inner workings of all
things involved. I shall give it a go again later and even try the patch.
But where do you want me to apply the patch - on the master branch or on
your pxe-services branch (
https://github.com/InfrastructureServices/dnsmasq/tree/pxe-services ) ?

Meanwhile, from a novice point of view and from what I know works in
dnsmasq, I have this query -

Could dnsmasq not be made to ignore the pxe-service lines or bypass the
corresponding logic from the ltsp-dnsmasq.conf when
1. is_tag_set("proxy") == "False" i.e ignore these lines -
pxe-service=tag:proxy,tag:!ipxe-ok,X86PC,"undionly.kpxe",ltsp/undionly.kpxe
pxe-service=tag:proxy,tag:!ipxe-ok,X86-64_EFI,"snponly.efi",ltsp/snponly.efi
pxe-service=tag:proxy,tag:ipxe-ok,X86PC,"ltsp.ipxe",ltsp/ltsp.ipxe
pxe-service=tag:proxy,tag:ipxe-ok,X86-64_EFI,"ltsp.ipxe",ltsp/ltsp.ipxe

2. and when is_tag_set("rpi") == "False" i.e. ignore this line or bypass
corresponding logic -
pxe-service=tag:rpi,X86PC,"Raspberry Pi Boot   ",unused
when dnsmasq is processing a request in *non-proxy mode* and the request is
from *X86-64_EFI clients*?

If possible, then everything would just work as expected for all scenarios
- *(BIOS or UEFI or RPI) and proxy*, *(BIOS or UEFI or RPI) and non-proxy*.
It may be possible to handle this just within dnsmasq.

Please do consider this if not already done so.

Thanks,
Shrenik

On Sat, 9 Oct 2021 at 03:43, Petr Menšík <pemensik at redhat.com> wrote:

> I have made some attempts at PXE booting. I have to say, it is a mess.
>
> Put my booting attempts at fedorapeople [1]. I have asked on #ipxe IRC
> channel. It seems pxe-service works only on biospc, client-arch == 0. I
> were able to make simple menu on my father's lenovo desktop and my work
> Thinkpad 490s. One instance of Raspberry 3. In Legacy mode, it works
> somehow well. You are even to make local boot menu entries. I made it
> possible to boot to memtest just fine.
>
> However, any my attempt in EFI mode to boot using menus failed. There is
> special function pxe_uefi_workaround, but to me it did not work. Current
> code did never return reply from pxe port request. Because my laptop
> does not send option 43 stuff in ipxe.efi request and I have not used
> proxy, it just does not answer. I were able to make it return something.
> It seems not well supported and should be avoided.
>
> Guys at ipxe channel told me EFI does not include option 43 menu
> support, which seems to be true. At that results, I think pxe-service
> should be in general avoided if you want to support EFI. Just use tags
> to offer first boot-file as ipxe.efi, then use ipxe script with possible
> menus inside. That seems to be more reliable and well documented way.
>
> I have fixed previous patch, it has to offer just based on boot item
> supplied type. Client arch is not always sent in a request, even when it
> is always present in discover, as I have noticed in Shrenik's dumps. I
> think that patch makes improvement and allows pxe-service work just for
> platforms related. Others should use dhcp-file with tags, depending on
> their clients.
>
> Custom setting of tags depending on option:client-arch seems to be more
> understandable and reliable.
>
> I have had enough of PXE today.
>
> Cheers,
> Petr
>
> 1. https://pemensik.fedorapeople.org/dnsmasq/
>
> On 10/7/21 23:10, Simon Kelley wrote:
> > As an aside the the discussion, can I just point out that I don't have
> > any way to test any of this dnsmasq functionality at the moment, and I'm
> > very rusty on the PXE spec, especially as it relates to EFI.
> >
> > I don't therefore have much to contribute to this discussion, but I do
> > think this is valuable work, and when you find a solution, I'll give the
> > resulting patchset my full attention.
> >
> >
> > Cheers,
> >
> > Simon.
> >
> > _______________________________________________
> > Dnsmasq-discuss mailing list
> > Dnsmasq-discuss at lists.thekelleys.org.uk
> > https://lists.thekelleys.org.uk/cgi-bin/mailman/listinfo/dnsmasq-discuss
> >
> --
> Petr Menšík
> Software Engineer
> Red Hat, http://www.redhat.com/
> email: pemensik at redhat.com
> PGP: DFCF908DB7C87E8E529925BC4931CA5B6C9FC5CB
> _______________________________________________
> Dnsmasq-discuss mailing list
> Dnsmasq-discuss at lists.thekelleys.org.uk
> https://lists.thekelleys.org.uk/cgi-bin/mailman/listinfo/dnsmasq-discuss
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/attachments/20211009/e2b2a852/attachment-0001.htm>


More information about the Dnsmasq-discuss mailing list