systemd-firstboot.service is an interactive wizard that asks for
locale, timezone, and root password when /etc/machine-id isn't
populated — i.e. every PXE boot of a mkosi-built image. It sits on
sysinit.target waiting for input that will never arrive, blocking
the agent service and every other downstream unit indefinitely.
systemd.firstboot=off on the kernel cmdline is the documented kill
switch; no image-side changes needed.
josh
026923075c