cron help

can someone please tell me what is the correct way to run a script every 1 hour?

* 1 * * * *
or
0 1 * * * *

Neither one, use: 0 * * * *

* 1 * * * means run every minute of the first hour of every day of every month

0 1 * * * means run at 1:00 am on every day of every month

honcho, should there not be 6 values and not 5?

Its only 5:

minute
hour
day
month
weekday

sorry, didnt know what i was thinking. so what would the values look like to run a script at 8am everyday? This is wrong is it not? 0 8 * * *

just do * 8 * * *

minute hour day month weekday <commandtorun>

minute 0-59
hour 0-23
day of month 0-31
month 0-12 (or names, see below)
day of week 0-7 (0 or 7 is Sun, or use names)

To run a script every one hour

0 0-23 * * * <command>

Should do the job 4 u..

thanks for all the help but I'm getting kind of confused. Just to clarify, what is the best way to run a script at 8am?

0 8 * * *

or

* 8 * * *

My bad dude:

Its 0 8 * * *
Will run it at 8 am....honcho and nazly are right.

hey it happens, one last question for you all. are the below values the same? i guess what i'm asking is will the do the same thing or is there a dif?


*/20 7-23 * * *

20 7-23 * * *

0 8 * * *
Will run the script at 8th hour 0th minute everyday everymonth alldayoftheweek
Simply will run at 08:00
So you have to use it in this manner

* 8 * * *
Will run the script at 8th hour everyminute everyday everymonth alldayoftheweek
Simply will run at 08:00, 08:01, 08:02,......, 08:58, 08:59 daily

I hope that makes sense

They are different..

*/20 7-23 * * *
Will run the script at each 0th,20th,40th minute of the hours 7-23
eg: 07:00, 07:20, 07:40, 08:00, 08:20, 08:40,......, 23:00, 23:20, 23:40

20 7-23 * * *
Will run the script at each 20th minute of the hours 7-23
eg: 07:20, 08:20,...., 23:20

I hope I'm correct

no, I think that */20 will run it every 20 minutes and just 20 will run it on the 20th minute of the hour.

*/20 mean every 20th minute of the hour.. So that will be 0th minute, 20th minute, 40th minute

Correct me if I'm wrong..

No your right.....Thats what I meant though....