1

Hello,

We are having issues with UEFI PXE boot from WDS. Our DHCP server is separate from WDS and they are on the same subnet. I’ve read that if they are on the same subnet, no DHCP options are needed, but I have tried with and without options and had the same issues.

What is happening is when selecting PXE boot from the dell boot screen, it attempts a PXE boot then goes to the Dell Support Assist screen. However if I select a legacy PXE boot it boots fine.

Any ideas where to look?

Thanks.

6 Spice ups
2

This is a known bug.

Supposedly fixed in the June updates.

You can also try

Open WDS console In the WDS server in the left pane and open Properties

Select the TFTP tab and uncheck Enable Variable Windows Extension

1 Spice up
3

Oh really? Do you know the KB for the update that is supposed to fix it?

4

Yeah it is the June 19 rollup

Addresses an issue that may prevent the Preboot Execution Environment (PXE) from starting a device from a Windows Deployment Services (WDS) server configured to use Variable Window Extension. This may cause the connection to the WDS server to terminate prematurely while downloading the image. This issue does not affect clients or devices that are not using Variable Window Extension.
1 Spice up
5

If it’s not what Justin’s talking about, make sure you’re running the minimum version of Windows Server for the UEFI boot you’re trying to do.

2 Spice ups
6

Thanks for the suggestions everyone. We have the fix update installed, and I tried un-checking Enable Variable Windows Extension as well. We do have the minimum version, we are on 2012 R2.

7

Do you get any errors or anything before it exits PXE boot? You might have to record the screen with your phone and then play back super slow. Sometimes the flash quicker than you can catch.

8

That’s a good idea, I’ll give that a try.

9

Hm, can’t seem to see an error message. As far as I can tell it sits on the Start PXE over IPv4 for a bit, then goes straight to the Dell Assist Screen.

10

Have you tried with multiple computers? If not, what model?

11

Yeah, I have two PCs I have been testing with. An Optiplex 3050 and a 3060. I think it is pretty strange, legacy boot works fine and launches right away. Almost like the server isn’t seeing the PXE request when it is a UEFI boot.

12

I’m assuming UEFI network stack is enabled (I believe it is by default on both models)

13

Yep, I don’t think the PXE boot option would be available if it wasn’t.

14

Can you grab a packet capture?

https://support.symantec.com/us/en/article.howto8573.html

It should look the same as in the link regardless of which PXE solution you’re using.

15

It looks similar, I see the client getting a DHCP offer from the DHCP server and the WDS server. Then after the ACK, I see proxyDHCP requests from the client to the WDS.

16

What was really odd, was I restarted to do a packet capture and it worked! I restarted to see if it was fixed, and it has only worked that once. I’m going crazy.

17

But no offer back to the client?

This is probably not going to matter, but restart your WDS server from the WDS MMC snap-in.

18

Also try disabling NetBIOS over TCP/IP in your WDS server’s NIC. I think everything is happening too fast for that to be the issue, but it’s one of the few things that affects UEFI but not legacy PXE.

19

There is an offer back to the client afterwards. I tried both suggestions but still no luck.

20

Grasping for straws at the moment, but let’s look at some of your settings.

In your WDS server’s properties, what do you have under these tabs:

PXE Response

Boot

Client