Same problem here, using pxelinux 6.03 as of 16.04.
I initially thought that it failed at an earlier PXE stage, as it alway booted to the local hard disk (exiting PXE), but that was only due to a 'default harddisk' within the configuration:
-------------------------------- default harddisk timeout 300 prompt 1
label harddisk localboot 0
label netboot kernel ... ... --------------------------------
Booting into 'netboot' worked well if specified as 'default netboot', but again, it would always select that default, regardless of prompt input.
Same problem here, using pxelinux 6.03 as of 16.04.
I initially thought that it failed at an earlier PXE stage, as it alway
booted to the local hard disk (exiting PXE), but that was only due to a
'default harddisk' within the configuration:
------- ------- ------- ------- ----
default harddisk
timeout 300
prompt 1
label harddisk
localboot 0
label netboot ------- ------- ------- ----
kernel ...
...
-------
Booting into 'netboot' worked well if specified as 'default netboot', but again,
it would always select that default, regardless of prompt input.