how to schedule the work in every two hours

[frederick van targero_1]

i tried many times by cron, but did not meet the expect. could any gentleman show me example?

thanks very much
frederick

[Huc_1 · Accepted solution]

Here is an example to do df every 2 hours.

to edit do crontab -e

add the following lines

00 2 * * * /usr/bin/df >> t.t
00 4 * * * /usr/bin/df >> t.t
00 6 * * * /usr/bin/df >> t.t
00 8 * * * /usr/bin/df >> t.t
00 10 * * * /bin/df >> t.t
00 12 * * * /bin/df >> t.t
00 14 * * * /bin/df >> t.t
00 16 * * * /bin/df >> t.t
00 18 * * * /bin/df >> t.t
00 20 * * * /bin/df >> t.t
00 22 * * * /bin/df >> t.t
00 00 * * * /bin/df >> t.t

this will run df every two hour and save output to file.

hope this not very usefull example will help you out.

J-P (Jean-Pierre)

[Huc_1]

Did it again ! should read my answer before sending then !

In the crontab file the first lines should read

/bin/df

like in the last lines.

Please No points for this reply !

J-P (Jean-Pierre)

[Bojan Nemec]

Frederick,

Acording to the crontab (5) man page the crontab entry can be:

0 0-23/2 * * * your2hourCommand
or
0 */2 * * * your2hourCommand
or
0 0,2,4,6,8,10,12,14,16,18,20,22 * * * your2hourCommand

I tested all 3 variants on the first field (minute) and they work.

Dont forget to finish the line with a new line! It seems that cron ignore lines which are not terminated by a linefeed

Bojan

[Muthukumar_5]

crontab entries can be defined to schedule work to be done in every two hours as,

0 0,2,4,6,8,10,12,14,16,18,20,22 * * *

where
first field indicates minute's
second one for hour setting

Example:
0 0,2,4,6,8,10,12,14,16,18,20,22 * * * date 1> /tmp/date_check 2>&1

* indicates that it will do in every day, every week-day and every month day's

[Fred Ruffet]

As long as linux cron has more features in time definition, the more easy way will be :
00 */2 * * * myjob

It will then run at odd hours.
If you want it to run at even hours, use :
00 1-23/2 * * * myjob

Regards,

Fred

[Senthilmurugan]

You can very well do the cronjob to be done for every 2 hours with the following entry in the cron list
Hello
Well you can do your job for every 2 hours using the cron.For this u can do the following in your command prompt:

#crontab -e
* */2 * * * /PATH/TO/COMMAND > /dev/null 2>&1


Now your job will be done for every 2 hours/

More can be available at:
#man 5 crontab

Regards,
Senthil Murugan