Super User is a question and answer site for computer enthusiasts and power users. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I'm trying to setup cron jobs for a website hosted on When I use the following it runs perfectly:

* * * * *

But whenever I make changes to these timestamps the script doesn't work.

If I use the following, it will not execute:

30 18 * * *

This automated script inserts data into the database.

Does anyone know why it's not working?

share|improve this question
There is not too much information to go on here. Your only hard data (the cron hour & min) are fine. What else is going on. Are you running these jobs as you? as root? Do /usr/lib/cron/cron.allow or cron.deny exist? How are you editing this file? Did you load it using crontab? – DaveParillo Oct 23 '09 at 15:18
as Dave says, nothing wrong with that. it should be running at 6:30pm. what are you expecting it to do? – quack quixote Oct 23 '09 at 16:38

Have you tried a simple test with something like,

10,20,30,40,50,0 * * * * date > /tmp/test-trace.txt

this should give you the 10min timestamps properly.
If it works for one time filter, it will work for any other...

Then, you need to look at how your script works.

share|improve this answer

Your crontab time (30 18 * * *) should work fine, as shown in the example here Have you considered there could be a problem with the script your using, does it have the right permissions?

share|improve this answer

If your cron executed if a wrong time, try restart your crontab!

$ service crond restart
share|improve this answer

You must log in to answer this question.