Cron Job Scheduel

[Eric Jacklin]

Hi Team,

I would like to schedule a cronjob which will execute the job every friday & Saturday every 30 Min.

So can i use 30 * * * 5,6 ?

[James R. Ferguson · Accepted solution]

Hi:

Yes, this is correct.

Regards!

...JRF...

[Dennis Handly]

No. That will do it every hour on the 30 minute mark. You need:
0,30 * * * 5,6

[Dennis Handly]

I guess we should have also asked, every 30 minutes starting when? At 0015?
15,45 * * * 5,6

[Eric Jacklin]

I want to start the job from 1.00 AM on Friday untill saturday and frequency is every 30 min

[Johnson Punniyalingam]

Crontab syntax :-
A crontab file has five fields for specifying day , date and time followed by the command to be run at that interval.
cat
* * * * * command to be executed
- - - - -
| | | | |
| | | | +----- day of week (0 - 6) (Sunday=0)
| | | +------- month (1 - 12)
| | +--------- day of month (1 - 31)
| +----------- hour (0 - 23)
+------------- min (0 - 59)

[James R. Ferguson]

Hi (again) Eric:

Duh! I'm sorry, Dennis is correct. You said *every* 30-minutes, not only at 30-minutes after the hour.

/* no points for my mistake nor this correction, please */

Regards!

...JRF...

[jaivinder]

The correct syntax for the crontab will be

0,30 * * * 5,6

[OldSchool]

Stated it two different ways, and the still isn't clear.

If you want "...every friday & Saturday every 30 Min" then:

0,30 * * * 5,6


If you want "...1.00 AM on Friday until saturday frequency s every 30 min"...

If you mean 1:00am Friday until midnight Friday (i.e. until Saturday), then:

0,30 1-23 * * 5
(this will not run at 00:00 Saturday)

If you mean something else, you're going to have explain it again, and be very precise in your description.

[Dennis Handly]

>OldSchool: If you mean 1:00am Friday until midnight Friday (i.e. until Saturday), then:
0,30 1-23 * * 5 # (this will not run at 00:00 Saturday)

Yes, 23*2 times. If you want to run one more time, you would need to add another line in crontab. Or you could expand the times in crontab and do the fine checking in your script.