@finvader Yes, set your boot order in all the machine’s firmware to Network First, HDD second. By default, if there are no jobs in FOG for said machine, it’s sent to the HDD to boot.
This “sending to hdd to boot” is controlled by the exit type in the FOG Web interface. The default can be set in FOG Settings. The setting can be altered per-host or mass-applied via Groups. The default is SANBOOT and works on most things, for most of the ones SANBOOT doesn’t work on, GRUB usually works. And then there are other options for the really difficult boxes.
I set the boot order in the firmware for 500 systems at my old job. I didn’t do it all at once, I modified the machines one by one as I needed to image them. Over the course of a year and a half, I got them all.
Of course I was also planning on modifying all new machines to boot to the network first as we received them - but then I got a new job.