Configuring crontab is very straightforward and easy, but not for everyone who's not used to with the format being used. Just let me give you what crontab format look like
0 * * * * /bin/bash /home/willysr/rsync_current.sh
This is an example of one of my cron job defined on my crontab. What does it do? Well, basically it will try to launch the rsync_current.sh script every day, every hour on minute 0, like 1:00, 2:00, 3:00, etc. Do you get the point? It's very straightforward.
The common format of crontab is (separated by space/tab):
minute hour day-of-month month day-of-week command-to-execute
Here's the allowed value for each field:
- minute : 0-59
hour : 0-23
day of month : 1-31
month : 1-12 (or names)
day of week : 0-7 (0 or 7 is Sun)
If you are too lazy to think about the command above, you can use a visual crontab editor from Corntab. It uses a JQuery to create a simple and easy to use interface for you to define your own crontab format. Pick on the pre-defined values or click on the date/minutes/hour/days available and the proper crontab format will be displayed in top of the page.
When you are ready to put them into your crontab, just launch a terminal and execute crontab -e and put all your crontab definition on that file and save it. It will be executed when the time defined in your crontab has come.
You can also send the crontab to someone else. Just put the email address and send it. Jobs done and everyone is happy. Now you shouldn't be afraid with crontab anymore, am i right?