After doing extensive testing with attempting to PXE boot Macs to a fog server, I created a solution which has worked for me so far (I had to make changes to the iPXE.iso found from iPXE website). Ultimately I was able to image over 30 lab machines running dual boot Mac OS and Windows 10

I had to create a bootable iPXE USB in order to get the Mac hardware to PXE boot to my server

Note that your mac must either have an Ethernet port built in, or you must use an Apple thunderbolt to Ethernet adapter

All the necessary files and a detailed READ ME can be found with this link
https://drive.google.com/file/d/1PDxx8qmN9UGKXMaUhy0xy3K4bvPh48KE/view?usp=sharing

Happy deploying

I’ve had this error appear as well. The error doesn’t make sense but for me it had to do with the size of the file I was uploading. When I installed fog initially maximum file size for file upload was set very low. Following this thread helped me resolve the same issue you are seeing. Basically you have to increase the file upload limit. I set mine to 3000mb.
https://forums.fogproject.org/topic/11875/snapin-upload-limit-of-8mb-is-too-small

@OmegaNull I haven’t had any luck using a usb to ethernet adapter but I have gotten the thunderbolt to ethernet adapter (made by apple) to work. Since this is included in the native drivers for mac OS, it works with iPXE.

@dylan123 My apologies for just now replying. I don’t check this very often! I have to go with raw capture because the organization I work at has bootcamped macs (very frustrating I know), and the only way to keep both partitions is to capture the disk as a whole. This is extremely limiting for fog, but it’s better than having to reinstall mac os and windows on each mac we have. Another issue I’ve come along is that Mac OS High Sierra and above forces APFS for ssds. Which I’m pretty certain is an issue for Fog. As far as the usb-c dongle, I’d bet that it would work as well if it’s made by Apple.

What are you using for a dhcp server? Do you have the option 66 and 67 defined globally or individually based on the vlan?

I’ve had this error appear as well. The error doesn’t make sense but for me it had to do with the size of the file I was uploading. When I installed fog initially maximum file size for file upload was set very low. Following this thread helped me resolve the same issue you are seeing. Basically you have to increase the file upload limit. I set mine to 3000mb.
https://forums.fogproject.org/topic/11875/snapin-upload-limit-of-8mb-is-too-small

@OmegaNull I haven’t had any luck using a usb to ethernet adapter but I have gotten the thunderbolt to ethernet adapter (made by apple) to work. Since this is included in the native drivers for mac OS, it works with iPXE.

@george1421 Have you followed the link I attached and tried the process of creating the USB? I made numerous attempts at creating a USB that allowed Macs to PXE boot. But here’s what I ended up having to change on the iPXE.iso taken from the iPXE website.

First I was able to open the iPXE.iso with winrar, then I logged onto my fog server and went to the /tftpboot folder. I then copied the IPXE.krn, and replaced the existing one on the iso. For whatever reason, the fog’s /tftpboot folder had a newer version of the file which allowed my devices to correctly boot.

The link I attached has the iso with the changes I made attached as well as the steps for creating a bootable usb for it.

After doing extensive testing with attempting to PXE boot Macs to a fog server, I created a solution which has worked for me so far (I had to make changes to the iPXE.iso found from iPXE website). Ultimately I was able to image over 30 lab machines running dual boot Mac OS and Windows 10

I had to create a bootable iPXE USB in order to get the Mac hardware to PXE boot to my server

Note that your mac must either have an Ethernet port built in, or you must use an Apple thunderbolt to Ethernet adapter

All the necessary files and a detailed READ ME can be found with this link
https://drive.google.com/file/d/1PDxx8qmN9UGKXMaUhy0xy3K4bvPh48KE/view?usp=sharing

Happy deploying