cron.allow file exists, it lists the users that may use
cron. If it does not exist, the
cron.deny file is checked.
cron.deny file exists, it lists the users that may not use
cron. This file is not consulted if the
cron.allow file exists.
If all users are denied the use of cron (as in your case, since the
cron.allow file exists, and is empty), only root is able to use
cron. This is the same that would happen if neither file existed.
The most common configuration is to have an empty
cron.deny file and no
cron.allow file. This would allow everyone the use of
This also applies to
at.allow for using
at to schedule commands.