You can enable logging for cron jobs in order to track problems. You need to edit the /etc/rsyslog.conf
or /etc/rsyslog.d/50-default.conf
(on Ubuntu) file and make sure you have the following line uncommented or add it if it is missing:
cron.* /var/log/cron.log
Then restart rsyslog
and cron
:
sudo service rsyslog restart
sudo service cron restart
Cron jobs will log to /var/log/cron.log