extra bytes padding in ethernet frame causes router confusion

[NiKiZe]

Since this is on the more technical level, I would suggest posting this to the ipxe mailing list for it to better reach the right audience.

But some more info might help here, Is this an issue with how iPXE creates the DHCP packet? an issue with the NII driver in iPXE, or an issue with the NII implementation in your firmware?
Do you have any machine with a nic that has native driver support if you use ipxe.efi instead?