STBoot is a custom bootloader provided by the u-root project. Its purpose is to be part of the firmware for the hosts. Depending on the scenario it either deployed as part of a disk image, as a UEFI application or as a coreboot payload.
STBoot will be executed automatically and starts configuring the network interface of the server. After downloading
stboot.ball from the provisioning server, several validation checks will be made. If successful, stboot will execute the boot configuration including the final operating system. The steps marked in grey are under development.