cronjob

[atul.kaggarwal]

How can i specify ifi want to run some process every 25 min

[Oviwan]

Hy

25 * * * * /path/to/jop

Regards

[atul.kaggarwal]

Thanks for reply.. Please now let me know how can we specify a job if i want to run it EVERY 1:30 Hours i.e. 90 min

[Dennis Handly]

You can't with crontab, only multiples or divisors of 60 minutes. Instead use at(1) and reschedule for 25 minutes later: at ... +25 minutes

Better yet, just use 30. For 30 you would use:
0,30 * * * * /path/to/jop

If you really really wanted to use 25, you would have to list all 57 values of 25 minutes in a 24 hour day.

[Yogeeraj_1]

hi

every 90mins would be: (suppose it started midnight: 1:30, 3:00, 4:30, 6:00, 7:30, 9:00, 10:30, 12:00, 13:30, 15:00, 16:30, 18:00, 19:30, 21:00, 22:30, 00:00)

#*******************************************************************************
# min|hour |day |month|day |script
# | |of mo| |of wk|
#----|-----|-----|-----|-----|--------------------------------------------------
#*******************************************************************************
30 1,4,7,10,13,16,19,22 * * * /path/to/job
00 3,6,9,12,15,18,21,00 * * * /path/to/job

#*******************************************************************************
# END OF TABLE day0->Sunday day6->Saturday
#*******************************************************************************

hope this helps!

kind regards
yogeeraj

[Dennis Handly]

If you want it to run every 90 minutes, you would have to list all 16 90 minute periods in a day. This is a simple two line crontab:
00 00,03,06,09,12,15,18,21 * * * command
30 01,04,07,10,13,16,19,22 * * * command

[Yogeeraj_1]

hi again,

if you want to "at" then it will be more simple since the time can be set relative to the last execution of the script.

e.g.

at -f /path/to/job +1.5 hours > /dec/null

(of course, you will need to set the appropriate permissions and include the command in the script itself)

hope this helps too!

kind regards
yogeeraj

[Dennis Handly]

>Yogeeraj: at -f /path/to/job +1.5 hours

You can't use 1.5 so you need: +90 minutes

[Oviwan]

You can also start a job once and include the following code:

i.e. for KSH:

while true
do

job....

sleep 5400

done

[Dennis Handly]

Oops, that's: at now +90 minutes

[Dennis Handly]

>Oviwan: start a job once...

This code does its work then waits 90 minutes. Depending on how long it takes, it won't be every 90 but may be close enough. If you want it accurate, you can get the start time and add 90 minutes and then sleep the difference when you recompute the current time when you are at the end of the loop.

>sleep 5400

This may be confusing. Either add comments or use:
sleep $(( 90 * 60 ))