systemd-update-utmp.service, systemd-update-utmp-runlevel.service, systemd-update-utmp − Write audit and utmp updates at bootup, runlevel changes and shutdown
systemd−update−utmp.service
systemd−update−utmp−runlevel.service
/lib/systemd/systemd−update−utmp
systemd−update−utmp−runlevel.service is a service that writes SysV runlevel changes to utmp and wtmp, as well as the audit logs, as they occur. systemd−update−utmp.service does the same for system reboots and shutdown requests.