systemd shutdown writes non-error message to stderr - causes email to be sent despite 'MailOnlyOnError'

[Graham Clinch]

Calling unattended-upgrade from cron with an Unattended-Upgrade::Automatic-Reboot-Time of "+5". This causes unattended-upgrades to run:

'/sbin/shutdown -r +5'

Systemd's shutdown writes an acknowledgement message to stderr:

Shutdown scheduled for Wed 2016-05-18 04:37:49 BST, use 'shutdown -c' to cancel.

Which cron picks up and emails - but I don't really want to know.

Is there any scope for unattended-upgrades to gobble shutdown's stderr message?

Or, perhaps this should be logged against systemd, since the shutdown message isn't really an obvious candidate for stderr?

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: unattended-upgrades 0.90
ProcVersionSignature: Ubuntu 4.4.0-22.40-generic 4.4.8
Uname: Linux 4.4.0-22-generic x86_64
ApportVersion: 2.20.1-0ubuntu2
Architecture: amd64
Date: Thu May 19 11:14:14 2016
PackageArchitecture: all
ProcEnviron:
 LANGUAGE=en_GB:
 TERM=xterm-256color
 PATH=(custom, no user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: unattended-upgrades
UpgradeStatus: No upgrade log present (probably fresh install)

[Timo (timo-1)]

I also noticed this bug recently. I find it very annoying to get system emails now whenever unattended-upgrades is scheduling a reboot. It should either be fixed in systemd (why are they writing an info message to stderr?) - or if it can't be fixed there, at least unattended-upgrades should redirect the output of the shutdown command to avoid these messages.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Balint Reczey (rbalint)]

I agree that it should be fixed in u-u. Patches are welcome.