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Edit File: systemd-sysupdate.timer

#  SPDX-License-Identifier: LGPL-2.1-or-later
#
#  This file is part of systemd.
#
#  systemd is free software; you can redistribute it and/or modify it
#  under the terms of the GNU Lesser General Public License as published by
#  the Free Software Foundation; either version 2.1 of the License, or
#  (at your option) any later version.

[Unit]
Description=Automatic System Update
Documentation=man:systemd-sysupdate.service(8)

# For containers we assume that the manager will handle updates. And we likely
# can't even access our backing block device anyway.
ConditionVirtualization=!container

[Timer]
# Trigger the update 15min after boot, and then – on average – every 6h, but
# randomly distributed in a 2h…6h interval. In addition trigger things
# persistently once on each Saturday, to ensure that even on systems that are
# never booted up for long we have a chance to to do the update.
OnBootSec=15min
OnUnitActiveSec=2h
OnCalendar=Sat
RandomizedDelaySec=4h
Persistent=yes

[Install]
WantedBy=timers.target