Cron every 2 mins

[Dewa Negara_4]

Hi All,

Sorry to ask a basic question. How can we run cron every 2 mins? Should list such 2,4,6,8,etc * * * *? Is there any better way?

Pls help.
Thanks and Best regards,
Negara

[A. Clay Stephenson · Accepted solution]

That's the way it is done. Some flavors of "improved" UNIX allow more flexibility but stick with the standard syntax and your crontab entries will work everywhere. Now have you considered what happens if for some reason the previous cron job is still running when the new one fires off?

[Patrick Wallek]

To run every 2 minutes, yes you need to list ALL even (or odd) numbered minutes.

Another way to do it would be via 'at'. At the end of your script you do an 'at scriptname now + 2 minutes' 'man at' for more information.

# cat script
#!/usr/bin/sh
do stuff
do more stuff
do even more stuff
at /dir/script now +2 minutes

[Yogeeraj_1]

hi Negara,

the most easy and dull way to do it is:
#***************************************
00 * * * * /home/yogeeraj/myscript.sh
02 * * * * /home/yogeeraj/myscript.sh
04 * * * * /home/yogeeraj/myscript.sh
06 * * * * /home/yogeeraj/myscript.sh
..
50 * * * * /home/yogeeraj/myscript.sh
52 * * * * /home/yogeeraj/myscript.sh
54 * * * * /home/yogeeraj/myscript.sh
56 * * * * /home/yogeeraj/myscript.sh
58 * * * * /home/yogeeraj/myscript.sh
#***************************************
# min|hour |day |month|day |script
# | |of mo| |of wk|
#----|-----|-----|-----|-----|-----------


kind regards
yogeeraj

[Victor Fridyev]

Hi,

You can run the script every minute, but to put into the script the following:

typeset -i N=0
N=$(date +%m)%2
if [ $N -ne 0 ]; then
exit
fi
#Your script etc

HTH

[Victor Fridyev]

Oops, sorry

There is a mistake in date format.

typeset -i N=0
N=$(date +%M)%2
if [ $N -ne 0 ]; then
exit
fi

According to the condition the script will exit every odd minute and will work every even minute.

HTH

[Peter Nikitka]

Hi,

you have to setup your cronjob every minute, but can prepend a one-liner to skip the add minute:
* * * * * [ $(date '+\%M 2\%\%p' | dc) -eq 1 ] || /path/2your/your-cron-script

The above construct will NOT have an exit status != 0 for skipped minutes.

mfG Peter

[Dewa Negara_4]

Hi All,

It looks fine to me now. Thanks alot for all your help.

Best Regards,
Negara

[Khashru]

Change in your script so that it runs in alternate minute and run that script once every hour.