In order to populate inventory with the network boot method in use, we need to pass a flag through from the network bootloader to the installed system.  See this ticket for background:
https://engineering.redhat.com/rt/Ticket/Display.html?id=126993

The best idea I've had is to set a flag on the kernel command line from within the cobbler pxe/efi/yaboot/whatever template.  A kickstart %post process could check kernel options for the flag, and drop something in a file on the installed system.  The inventory script would check for that file, and set the Key/Value appropriately.

The only thing we've implemented so far is that the Key is "NETBOOT_METHOD".

We can add the flags to the cobbler templates as a local change, so it's the flag detection and inventory script pieces we'll need done.

The kernel option name needs to be short, meaningful, and not conflict with existing kernel or anaconda options.  Ideas?