Hi guys,

Finally got some time to look into it.

Long story short, this smells like infrastructure problem.
SARR passes over 546/547 port pair. That is between UEFI PXE client and 
DHCP server (even if it is the same machine).
The next packet is essentially a Boot Server choice step. UEFI PXE 
client sends a unicast discovery packet towards Boot server (same 
machine, same address) coded as DHCP Request.
The release packet is a direct reaction to 3 second timeout (see time 
diff between packet 9 and 11).

See section 2.2.1 in PXE spec: 
http://www.pix.net/software/pxeboot/archive/pxespec.pdf

Please verify that your WDS service is running correctly, since clearly 
there is no reaction to that packet from Boot server.



On 28-Jun-21 22:05, LathaKannan Arumugam via groups.io wrote:
> Can you please help us on this issues?
> Get Outlook for Android <https://aka.ms/AAb9ysg>
> ------------------------------------------------------------------------
> *From:* devel@edk2.groups.io <devel@edk2.groups.io> on behalf of 
> LathaKannan Arumugam via groups.io <larumugam=microsoft.com@groups.io>
> *Sent:* Friday, June 25, 2021 1:11:42 PM
> *To:* Bret Barkelew <Bret.Barkelew@microsoft.com>; Rabeda, Maciej 
> <maciej.rabeda@linux.intel.com>; devel@edk2.groups.io 
> <devel@edk2.groups.io>
> *Subject:* Re: [EXTERNAL] Re: [edk2-devel] NetworkPkg: Unexpected DHCP 
> RELEASE after PXE server reply on IPv6
>
> Any inputs?
>
> We kind of blocked on this for a week. Kindly look into packet capture 
> and suggest a path forward.
>
> *From:* LathaKannan Arumugam
> *Sent:* Friday, June 25, 2021 9:23 AM
> *To:* Bret Barkelew <Bret.Barkelew@microsoft.com>; Rabeda, Maciej 
> <maciej.rabeda@linux.intel.com>; devel@edk2.groups.io
> *Subject:* RE: [EXTERNAL] Re: [edk2-devel] NetworkPkg: Unexpected DHCP 
> RELEASE after PXE server reply on IPv6
>
> Attached packet captured from server.
>
> *From:* Bret Barkelew <Bret.Barkelew@microsoft.com 
> <mailto:Bret.Barkelew@microsoft.com>>
> *Sent:* Friday, June 25, 2021 9:19 AM
> *To:* Rabeda, Maciej <maciej.rabeda@linux.intel.com 
> <mailto:maciej.rabeda@linux.intel.com>>; devel@edk2.groups.io 
> <mailto:devel@edk2.groups.io>; LathaKannan Arumugam 
> <larumugam@microsoft.com <mailto:larumugam@microsoft.com>>
> *Subject:* Re: [EXTERNAL] Re: [edk2-devel] NetworkPkg: Unexpected DHCP 
> RELEASE after PXE server reply on IPv6
>
> + @LathaKannan Arumugam <mailto:larumugam@microsoft.com>
>
> - Bret
>
> ------------------------------------------------------------------------
>
> *From:*Rabeda, Maciej <maciej.rabeda@linux.intel.com 
> <mailto:maciej.rabeda@linux.intel.com>>
> *Sent:* Friday, June 25, 2021 7:40:16 AM
> *To:* devel@edk2.groups.io <mailto:devel@edk2.groups.io> 
> <devel@edk2.groups.io <mailto:devel@edk2.groups.io>>; Bret Barkelew 
> <Bret.Barkelew@microsoft.com <mailto:Bret.Barkelew@microsoft.com>>; 
> Bret Barkelew <Bret.Barkelew@microsoft.com 
> <mailto:Bret.Barkelew@microsoft.com>>
> *Subject:* [EXTERNAL] Re: [edk2-devel] NetworkPkg: Unexpected DHCP 
> RELEASE after PXE server reply on IPv6
>
> Looking at it. Any chance to get Wireshark trace for this scenario?
>
> On 25-Jun-21 09:25, brbarkel via groups.io wrote:
>
>     Just poking this to see if anyone has any ideas. Thanks!
>
>