CODE EXAMPLE FOR SHELL

how to check cron is running or not

$ systemctl status cron              # checks if cron is running

$ sudo systemctl enable cron.service # enable cron to run on boot
$ sudo systemctl start cron.service  # start cron now

$ sudo crontab -l                    # show all currently running cron jobs 
$ sudo crontab -u panda -l           # show all cron jobs running for user panda