DHCP Server Settings
The boot file names you put in option 67 are identical on both versions —
1.5 and 1.6 package the same iPXE binaries, so a dhcpd.conf or
kea-dhcp4.conf written for one works unchanged on the other. What differs is
how the UEFI boot script reaches the client, and the --boot-delay option,
which 1.5 does not have.
Which version am I on?
Check FOG Configuration → FOG Settings → General → FOG_VERSION in the web UI, or the version string printed at the top of
installfog.sh.