Nextcloud: last background job ran days ago

daniele@mikweb: ~/errors — less nextcloud-last-background-job-ran-ago-cron.md

What the message looks like

Last background job execution ran 3 days ago. Something seems wrong.

Background jobs set to AJAX or Webcron instead of Cron.
No crontab entry for the web server user, or the entry is in root's crontab.
cron.php aborts, e.g. because of APCu in the CLI, the wrong PHP version or memory limit.
systemd timer disabled or not moved along after a migration.
Container setup without a separate cron container.

Show the configured background job mode
sudo -u www-data php /var/www/nextcloud/occ config:app:get core backgroundjobs_mode
Show the web server user's crontab
crontab -u www-data -l
Run cron.php once by hand and see errors
sudo -u www-data php -f /var/www/nextcloud/cron.php; echo "exit $?"
Check existing systemd timers
systemctl list-timers | grep -i nextcloud

Set the mode to Cron: occ background:cron.
Create the crontab for www-data: */5 * * * * php -f /var/www/nextcloud/cron.php.
Fix errors from the manual run, e.g. set apc.enable_cli=1.
Alternatively use a systemd timer that runs every 5 minutes as www-data.
After a few minutes check in the admin settings that the time updated.

AJAX only runs jobs when someone uses the web UI, and only one per page load. With little usage jobs pile up.

No. cron.php must run as the owner of the Nextcloud files, otherwise it creates files with wrong permissions and Nextcloud aborts.

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