[aylux2121]

No, he says that he flashed SD cards.

> I flashed each of the Raspberry Pis using the same SD card, then I could close the case and take a note of each MAC address and serial number for later on.

But if flashing SD cards, then why do we need network boot? Or, if we have network boot, why do we need to use SD cards?

[paxswill]

The easiest way to perform the flash is by booting into Raspbian and performing the process interactively. Without this one-time process, you can't netboot, as the default setting is the SD card, then USB: https://www.raspberrypi.org/documentation/computers/raspberr...