On Sat, Feb 10, 2024 at 8:05 PM Robert McBroom via users <users@lists.fedoraproject.org> wrote:
I typically boot in mode 3 to a terminal. Fedora f39 going to lxde as
the desktop. Today with a cold boot and entering  the user login the
following message showed

--

System is going down. Unprivileged users are not permitted to log in
anymore , for technical details see pam_nologin(8)

--

Further messages indicated that some updates were being installed. After
some minutes the system rebooted.

Everything known has been done to prevent any automatic updates with
manual dnf being used as needed. The pam_login module looks for the
existence of

/etc/nologin or

/var/run/nolongin

What is updating files without a command  and writing these entries?

Maybe firmware updates -- these seem to differ depending on the type
of device and vendor.   

From <https://en.wikipedia.org/wiki/Fwupd>:

It [fwupd] is designed primarily for servicing the Unified Extensible 
Firmware Interface (UEFI) firmware on supported devices via EFI 
System Resource Table (ESRT) and UEFI Capsule, which is supported 
in Linux kernel 4.2 and later. [...] ESRT allows the firmware to expose 
updatable components to the operating system, which can pass a 
UEFI capsule with updated firmware for processing and installation 
on the next boot.

Journalctl may have more details, if you can find them amid the mass of detail 
journalctl provides.   It would be nice to have a mechanism that highlights entries 
that are new to the current boot but have not appeared in previous boots.

--
George N. White III