some UEFI systems require more options

[chrwei]

Your write up helped a lot, but some thing didn't work out of the box. This is what I found that works.

Add this to see info like client-arch numbers in the log, and to verify what boot file is being sent

log=dhcp

proxmox UEFI VM requires this line (and also requires a VirtIO RNG manually be added to the VM, but that's a proxmox thing)

dhcp-match=set:efi-x86_64,option:client-arch,9

a celeron n4000 based mini PC with Realtek lan I have requires BOTH these lines, which adds a prompt, but only the "2" line works. Removing the first line causes it to fail.

Proxmox VM also works with these 2 lines and NO dhcp-match or dhcp-boot lines at all, but proxmox VM works with either of these

pxe-service=x86-64_EFI,"PXELINUX (EFI) 1",efi64/syslinux.efi
pxe-service=7,"PXELINUX (EFI) 2",efi64/syslinux.efi

So, you could remove all the match/boot options and just add more services options, it seems, but I haven't tested with a wide variety of hardware.