iPXE and USB-C

[speleo14]

Hi list

I am using iPXE to PXE-boot Macs to a WDS server in order to install Windows on them. For older Macs (with BIOS-emulation), I use the prebuilt ipxe.iso-Image, for the newer ones (the ones with EFI-boot) I use an ipxe.efi executable on a USB stick. This has worked fine so far, even for Mac laptops that do not have a built-in NIC and where I have to use a Thunderbolt-ethernet or USB-ethernet adapter.

However, the new MacBooks Pro now only have combined USB-C/Thunderbolt 3 ports, and no matter what kind/brand of network adapter I use, I am not able to PXE boot them. Either the network adapter is not seen at all, or it is seen as down, or it is seen and up, but the configuration fails.

Unfortunately, I am not really an expert when it comes to PXE-booting... I suspect that maybe a driver for USB-C is missing? Any ideas what I could try? This is really a show-stopper for us.

Thanks, Tina