This was indeed a BIOS issue. Dell released 1.6.1 for the 5591 on Feb. 25. We have updated to 1.6.1 and the UEFI boot now works.
Posts made by EricLA2K
RE: Dell 5591: TFTP works for Legacy but not UEFI
Typo indeed. That should be “ipxe.efi.”
Here is a link for both a capture with Legacy followed by UEFI and UEFI only: https://drive.google.com/open?id=1_q2vTgCfB5P433nz0lQphR2v5W92d_AW
Dell 5591: TFTP works for Legacy but not UEFI
We just received a large batch of Dell E5591 laptops. We are wanting to use UEFI to install and image these laptops. We can PXE boot these to our Fog server (hosted on Ubuntu 16.04) using Legacy boot. Unfortunately, this does not work when we try to PXE boot using UEFI.
the laptop gets an IP from the DHCP the fog IP and the ipxe.efi file name from the Fog server, but never appears to try the TFTP connection.
I have used tcpdump on the Fog server and can watch the full transaction for the DHCP (ports 67 and 68) and TFTP (port 69) and everything works great when booting via Legacy. For the UEFI boot, I can see the laptop receives the DHCP IP, the Fog server IP and the file to download (ipxe.efi), but the laptop never appears to try the TFTP connection.
Also, briefly displayed during the PXE UEFI boot, the following is displayed:
Server IP address is 192.168.10.10. NBP filename is pxe.efi NBP file size is 0 bytes. PXE-E99: Unexpected network error.
I know this is likely a laptop issue and not Fog, but curious if anyone else has experienced a similar issue. We have verified the laptop is up to date with Dell firmware.