Basics of a CRON Job

Creating a simple cron job – format: A B C D E /path/file, where:

VariableTypePossible ValuesSample Values
AMinute0-5930 = every 30 minutes
BHour0-230 = 12 AM
CDat of Month1-3115 = 15th day of a month
DMonth of Year1-124 = April
EDay of Week0-60 = Sunday

To place scripts as scheduled tasks, edit the /etc/crontab file:

vim /etc/crontab

This Cron entry runs the script /path/to/file.sh as root every 0,5,10,15,20,25,30,35,40,45,50,55 minute of every hour, day, month, and day of week: