Crontab never running while in /etc/cron.d
Files in /etc/cron.d
need to also list the user that the job is to be run under.
i.e.
0,15,30,45 * * * * root /backup.sh >/dev/null 2>&1
You should also ensure the permissions and owner:group are set correctly (-rw-r--r--
and owned by root:root
)
Another thing I've observed is that the file in /etc/cron.d
cannot have an extension. In my particular case, I had a symbolic link:
# my-job.crontab
* * * * * root echo "my job is running!" >> /tmp/my-job.log
$: ln -sf /home/me/my-job.crontab /etc/cron.d/
# This did not work -> job would not run
$: ln -sf /home/me/my-job.crontab /etc/cron.d/my-job
# This did work -> job ran fine
File name restriction are documented at run-part man page: http://manpages.ubuntu.com/manpages/xenial/man8/run-parts.8.html, one can pass an --regex option to override the file format.
The default cron behavior however stayed without extensions, see comments under: https://bugs.launchpad.net/ubuntu/+source/debianutils/+bug/38022
I think you probably just missing a necessary blank line from the end of your cron file. I had the same issue, but after checking everything listed here (user permissions, filename, cron version etc.), I realized that I did not have line break after the last entry in my /etc/cron.d/own_cron
and that causes the entire file being ignored.