linux man page for systemd-system-update-generator

SYSTEMD-SYSTEM-UPDATE-GENERATOR(8)			  systemd-system-update-generator			SYSTEMD-SYSTEM-UPDATE-GENERATOR(8)

NAME
       systemd-system-update-generator - Generator for redirecting boot to offline update mode

SYNOPSIS
       /lib/systemd/system-generators/systemd-system-update-generator

DESCRIPTION
       systemd-system-update-generator is a generator that automatically redirects the boot process to system-update.target, if /system-update
       exists. This is required to implement the logic explained in the systemd.offline-updates(7).

       systemd-system-update-generator implements systemd.generator(7).

SEE ALSO
       systemd(1), systemd.special(7)

systemd 237													SYSTEMD-SYSTEM-UPDATE-GENERATOR(8)