Unattended-upgrade-shutdown rebooting system without warning

Ubuntu Version: 26.04

Desktop Environment (if applicable):
GNOME

Problem Description:
Unattended-upgrade-shutdown rebooting system without warning

Example:

Jul 26 19:33:38 Ubuntu-PC1 sbkeysync[3929]: /usr/share/secureboot/updates/dbx/dbxupdate_x64.bin
Jul 26 19:33:38 Ubuntu-PC1 sbkeysync[3929]: Inserting key update /usr/share/secureboot/updates/dbx/dbxupdate_x64.bin into dbx
Jul 26 19:33:38 Ubuntu-PC1 systemd[1]: Started unattended-upgrades.service - Unattended Upgrades Shutdown.
Jul 26 19:33:38 Ubuntu-PC1 unattended-upgrade-shutdown[4543]: /usr/share/unattended-upgrades/unattended-upgrade-shutdown:250: PyGIDeprecationWarning: GLib.unix_signal_add is deprecated; use GLibUnix.signal_add instead
Jul 26 19:33:38 Ubuntu-PC1 unattended-upgrade-shutdown[4543]: GLib.unix_signal_add(GLib.PRIORITY_DEFAULT, sig,
Jul 26 19:33:44 Ubuntu-PC1 cron[4869]: (CRON) INFO (Running @reboot jobs)
Jul 26 19:34:04 Ubuntu-PC1 systemd[5048]: Reached target gnome-session-shutdown.target - Shutdown running GNOME Session.
Jul 26 19:34:04 Ubuntu-PC1 systemd[5048]: Starting gnome-session-restart-dbus.service - Restart DBus after GNOME Session shutdown…
Jul 26 19:34:04 Ubuntu-PC1 systemd[5048]: Stopped target gnome-session-shutdown.target - Shutdown running GNOME Session.
Jul 26 19:34:04 Ubuntu-PC1 systemd[5048]: Started gnome-session-restart-dbus.service - Restart DBus after GNOME Session shutdown.
Jul 26 19:34:14 Ubuntu-PC1 systemd[5048]: Reached target shutdown.target - Shutdown.
Jul 26 20:16:03 Ubuntu-PC1 steam[40067]: Looks like steam didn’t shutdown cleanly, scheduling immediate update check
Jul 26 20:36:20 Ubunntu-PC1 kernel: secureboot: Secure boot enabled

The default in /etc/apt/apt.conf.d/50unattended-upgradesappears to be set to True if the line

//Unattended-Upgrade::Automatic-Reboot "false";

is not commented out.

This has happened to me twice at random times of the day, luckily it did not cause me to lose any data.

Relevant System Information

Brand new Ubuntu 26.04 system with all current updates and upgrades. The logs show multiple attempts to upload dbxupdate_x64.bin to NVRAM but there is not enough space triggering “Cannot allocate memory" logs.

What I’ve Tried:

uncommented Unattended-Upgrade::Automatic-Reboot “false”;

I have also disabled all current and future updates of dbx files. The constant attempts to upload may of contributed to a Kernel level event triggering unattended-upgrade-shutdown rebooting system without warning

So far so good.

1 Like

By default unattended-upgrades does never reboot any Ubuntu system, also note that the script /usr/share/unattended-upgrades/unattended-upgrade-shutdownis usually being invoked by systemd to make sure that any still running unattended-upgrades processes are gracefully stopped before shutdown of the machine.

This script is very likely not the cause of the shutdown but only fallout of the shutdown happening while an unattended upgrade was still running … have you checked the log above the snippet you pasted ?

1 Like

It would appear the log entries looked suspicious, the actual crash/reboot happened before the logs were generated. No logs of the event exist for some reason prior to 19:33:23.