How to Set up a Crontab File on Linux

Cron is a job scheduling subsystem for linux. It is used for scheduling repeating jobs. If you wish to schedule a one shot job use the at subsystem. All users on a linux box may set up cron jobs provided they are allowed by the...

Method 1 of 2:

Setting up the File

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Using your favourite editor, create a cron file with a line for each job you wish to schedule, in the format: m h d m w command
1. m minute
2. h hour
3. d day of month
4. m month 1-12
5. w weekday 0-7, Sun,Mon, etc (Sunday = 0 = 7) It is easy to remember if you think of the way one would say a date: Wednesday, July 29, at 10:30, then reverse the order.
How to Set up a Crontab File on Linux Picture 2

Load your file into crontab: crontab yourfile

Method 2 of 2:

Trying an Example

Create a file testCron.txt containing the following lines:
1. # do this every 10 minutes
2. */10 * * * * date >> ~/testCron.log
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Load it into cron: crontab testCron.txt
Wait 30 minutes, check testCron.log, if it works it will update your file with a time stamp 3 times.
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Remove the crontab so that it does not run forever: crontab -r