cron for every 3 hours but when check with cron log it shows it runs after every 1 min
Please any one help why it runs on every min when it only run on given time.

[root@appser ~]# crontab -u prod -l
* */3 * * * /backup/backup.sh

[root@appser ~]# tail /var/log/cron
Jun 10 21:11:01 appser crond[18064]: (prod) CMD (/backup/backup.sh)
Jun 10 21:12:01 appser crond[18072]: (prod) CMD (/backup/backup.sh)
Jun 10 21:13:01 appser crond[18107]: (prod) CMD (/backup/backup.sh)
Jun 10 21:14:01 appser crond[18161]: (prod) CMD (/backup/backup.sh)
Jun 10 21:15:01 appser crond[18178]: (prod) CMD (/backup/backup.sh)
Jun 10 21:16:01 appser crond[18221]: (prod) CMD (/backup/backup.sh)
Jun 10 21:17:01 appser crond[18249]: (prod) CMD (/backup/backup.sh)
Jun 10 21:17:58 appser crontab[18294]: (root) LIST (prod)
Jun 10 21:18:01 appser crond[18296]: (prod) CMD (/backup/backup.sh)
Jun 10 21:19:01 appser crond[18335]: (prod) CMD (/backup/backup.sh)

Give it a minute for the relevant hour. Something like

Hello billy,
Thanks for your reply, but we have already test this and again checked that it runs every min, and then changed cron enrtry like this
* 0,3,6,9,12,15,18,21 * * * /bin/sh /backup/backup.sh >/dev/null 2>&1

but not get any reason why it runs every min.
Also I have checked with google and few linux forum's but not getting any satisfied answer's from them.

Can you give any reason why it's happen
Please help me to resolve this

Thanks

Which crontab are you editing and how?

Hello billy,

[root@appser ~]# rpm -qf /usr/bin/crontab
vixie-cron-4.1-72.el5

and OS version is
[root@appser ~]# cat /etc/issue
CentOS release 5.2 (Final)
Kernel \r on an \m

Your new entry still says every minute (*) for every 3rd hour. You must specify a specific minute value, not a wildcard.

See http://www.adminschoice.com/docs/cro...Crontab%20file

Thanks chrism01,
Now we have resolved this

Thanks

How did you resolve it?