This is a really common antipattern people seem to tend toward with cron.
Cron sends you an email with the output of your script, if it generates any output. People often redirect output to /dev/null to prevent cron from sending the email. This is bad because now the output of your script is lost entirely. Even if the script has some built-in logging, it might generate errors before it gets the log file opened and those are lost. It also might crash in a way that doesn't get written to the logging mechanism.
At a bare minimum, you should just remove 2>&1 >/dev/null to start receiving the email. (and also, test your mail setup using a temporary cron job like 1 * * * * echo "Test" )
The next better solution is to change it to >> /var/log/myscript/current.log and then also set up something to rotate the log files (like logrotate) and also make sure to create that directory with permissions that the script user is allowed to write to it. By only redirecting STDOUT of the script, any errors or warnings it writes to STDERR cause you to get an email, and if there are no errors/warnings the output goes to the log file and no email gets sent.
Neither of those changes solve the root problem though, which is that when cron runs your script it does so with a different environment than you have on the command line. What you really want is a way to run the script with a consistent environment, and log it. The "ultimate solution" is to define your task in some kind of service manager, and then use cron to occasionally start it. For instance, you could use systemd and define a service that doesn't restart, then use systemctl start my_custom.service in your cron job. Now you can test independent of cron, and your tests will have the same exact environment, and be logged by the service manager. As extra bonuses, you are protected from accidentally running your script twice at once, and you get a clean way to stop a running cron job without the danger of stale pid files.
I don't particularly advocate systemd myself, but thankfully there are lots of alternatives:
(but installing and configuring a service manager is a bigger task than just using systemd if your distro is based on systemd) Each of these allows you to define a service that doesn't restart. Then you use a shell command to issue a "run once" directive to the supervisor, which runs the task as a child. Now you can easily launch the jobs yourself and see all the errors in the log, and then add that command to the crontab and know that it will run identically when cron starts it.
Back to your original problem, once you get some logging you are likely to discover it is a permission problem or a upgraded module in the system perl.
MAILTO = [email protected]in crontab file to be notified about the source of the problem. Please visit webpage for explanation.