I can't get a PXE client to boot properly from a distribution point enabled for PXE. I understand a lot of the technical details here, so bear with me.
The client is booting from \SMSBoot\x64\wdsmgfw.efi, as it's a 64bit UEFI machine. This wdsmgfw.efi file is downloading just fine.
The first thing it does is direct the client to download \Boot\x64\wdsmgfw.efi. This is the standard file which is part of WDS. The first thing this file does is attempt to load \Tmp\x64uefi{29BCDCF4-A8D0-4EA9-B197-87ED8FA6F977}.bcd. Immediately after that, I get this error message on the client:
The Windows Boot Configuration Data (BCD) file from the PXE server does not contain a valid operating system entry.
Now, I know the problem here. The BCD file it is downloading has no boot system images in it. And so I get the error. It looks like SCCM generates it's own set of BCD files in \SMSTemp. These files have the SMS boot images configured in them.
So, if I copy one of the SMSTemp files into Tmp, and rename it to x64uefi*, the client successfully boots into the SCCM WinPE image.
This raises some questions. My suspicion here is that the client is supposed to directly load \SMSTemp\ files, and not \Tmp\ files. And yet it is not. I'm guessing this is because \SMSBoot\x64\wdsmgfw.efi is loading \Boot\x64\wdsmgfw.efi, which isn't SCCM related, and is then going along with the normal WDS process.
What's up here? Why would my PXE clients be loading \SMSBoot\x64\wdsmgfw.efi, and then immediately jumping to \Boot\x64\wdsmgfw.efi?