systemd-user-sessions.service, systemd-user-sessions - Permit user logins after boot, prohibit user

       systemd-user-sessions.service is a service that controls user logins through pam_nologin(8). After basic
       system initialization is complete, it removes /run/nologin, thus permitting logins. Before system
       shutdown, it creates /run/nologin, thus prohibiting further logins.

       systemd-user-sessions.service, systemd-user-sessions - Permit user logins after boot, prohibit user
       logins at shutdown

systemd(1), systemd-logind.service(8), pam_nologin(8)

systemd 257.7                                                                   SYSTEMD-USER-SESSIONS.SERVICE(8)

       systemd-user-sessions.service

       /usr/lib/systemd/systemd-user-sessions