ugrd runs the init script generated in the build dir. In cases where agetty is needed, all but basic initialization and the final switch_root are performed in init_main.sh.
UGRD should prompt for relevant input or warn if devices are missing at runtime.
If UGRD does not print its version after the kernel calls /init, the
ugrd.base.consolemodule may need to be enabled to start an agetty session.
In the event of a failure, modules will either fail through, or re-exec the init script.
The recovery cmdline arg will allow a shell to be spawned in the event of a failure. This is useful for debugging.