Booting FreeNAS USB Stick on R720xd - VincentSaelzler/HomeLab GitHub Wiki
Conjecture
I believe that if no other HDDs/USB Sticks/SSDs are detected, it will eventually boot from the FreeNAS USB.
To be clear, I mean no other HDDs/USB Sticks/SSDs. That includes non-bootable ones.
Full Set of Steps That Definitely Worked
Firmware 2.7.0
Remove all HDDs and USB Sticks
Go to lifecyclemanagement. Clear/Reset
Once Powered Off, Power On
There will be a power testing boot, and ultimately it will say no boot device
Power Off
Plug in BOOTABLE FreeNAS usb to FRONT panel
Don't push anything. It will try and boot via network, then boot from the FreeNAS USB
Once in installer interface, THEN open lid and insert USB drive that is target of installation.