CRON

CRON is a utility program that comes with almost all Linux distributions. CRON is used to schedule/automate any script or program. CRONTAB is user interface for CRON.Every user has its own crontab which helps to schedule user specific tasks.

Open crontab

$ crontab –e

Edit crontab

Commands used in VIM can be used to edit and save

Display crontab

$ crontab -l

Format used in crontab entry

Example

00 07 * * 1-5 /sbin/diskusages.sh

MIN HOUR MDAY MON DOW COMMAND

MIN =  Minute 0-60

HOUR = Hour [24-hour clock] 0-23

MDAY = Day of Month 1-31

MON = Month 1-12 OR jan,feb,mar,apr ...

DOW =  Day of Week 0-6 OR sun,mon,tue,wed,thu,fri,sat

COMMAND = Any valid command that need to be ran.