crontab

sangfroid · 01-29-2013, 01:46 PM

Hi,

Just a quick question.

Is the following crontab supposed to run on every 5 minutes of monday between 10-12

*/5 10-12 * * 2

?

truecipher · 01-29-2013, 02:04 PM

-- -- -- -- --
min hr dom mon dow
0-59 0-23 1-31 1-12 0-6

min: Minute
hr: Hour
dom:: Day of Month
mon: Month
dow: Day of Week

*/5 would run every 5 minutes
but I don't think you can specify time as you wish. You may have to add several lines:
One line for each hourly block:

*/5 10-11 * * 2
*/5 11-12 * * 2

suicidaleggroll · 01-29-2013, 02:06 PM

I'm not sure about the 10-12 part, but you could just specify 10,11,12 instead. Also, the day of week value has Sunday at 0, so 2 would be Tuesday.

*/5 10,11,12 * * 2

If you want to test it, just add a dummy entry like so:

Code:

*/5 10,11,12 * * 2 echo $(date) >> /home/user/crontest.out

Replacing the 2 for the day of week with the current day. Then just check crontest.out after the day is over to see which times were run.

colucix · 01-29-2013, 02:32 PM

The syntax is correct even for the hour field.

Code:

*/5 10-12 * * 2

Just take in mind that it will run till 12:55, not 12:00 as maybe supposed to do. Regarding the day of the week, the only caveat is that if you specify both the day of the month AND the day of the week, the effect is additive: it means it will run on both the specified days of the month AND every specified day of the week. Since the day of the month is not restricted here, it will run only on every Tuesday (not Monday as mentioned in the first post).

Rupadhya · 01-29-2013, 02:54 PM

There is a simple web app that allows you to edit your crontab.

It is at http://www.corntab.com/

From the web page.

Corntab is a simple crontab web GUI
With Corntab you can ensure that you always have the correct crontab syntax.

Don't worry about forgetting the proper crontab format for a particular Linux distribution because Corntab let's you click on all of the crontab options and outputs your crontab entry in real-time.

There is nothing to install.

mlbx · 01-30-2013, 04:36 PM

If you enter the crontab values at the CronBuddy website you will see a forward schedule of run times.

truecipher · 01-31-2013, 05:11 AM

Re: Corntab and CronBuddy

Maybe its just me but way over half the fun of Linux is using the terminal and scratching notes in a notebook of different commands and arguments. I duckduck things and read man pages and take notes for future reference.

example:

Code:

mpg123 -w name.wav name.mp3

...is so much cooler than using a GUI software package. Also, it impresses women worth knowing...

vipin310379 · 01-31-2013, 12:07 PM

*/5 10-12 * * 2
(it will run the job on Tuesday from 10.00 to 12.55 every five minutes interval)

*/5 10-11 * * 1
(it will run the job on Monday from 10.00 to 11.55 every five minutes interval)

mlbx · 04-02-2013, 06:02 AM

Quote:

Originally Posted by mlbx

If you enter the crontab values at the CronBuddy website you will see a forward schedule of run times.

This interactive cron simulator is now athttp://www.dataphyx.com