The RPi 3 and late revisions of the RPi 2 support PXE on the built-in Ethernet adapter: https://www.raspberrypi.org/documentation/hardware/raspberrypi/bootmodes

The RPi 3 and late revisions of the RPi 2 support PXE on the built-in Ethernet adapter: https://www.raspberrypi.org/documentation/hardware/raspberrypi/bootmodes/net.md https://www.raspberrypi.org/documentation/hardware/raspberry... The RPi 4 has a boot process with a programmable boot ROM that should allow for a more "real" bootloader like uboot in the long term, but currently PXE isn't supported.