'Test run cron entry

I added a cron job recently, but made a mistake in the path while giving the command and hence, the job never succeeded. Is there some way to test the cron changes we have done?

Please note that I had indeed copied and pasted the command from my command line and it was just an stray keypress that caused this.

linuxunixcroncrontab


Solution 1:[1]

This question has also been asked on serverfault and has garnered a couple additional answers

The following is a paraphrased version of Marco's solution: (Not sure if best etiquette is not providing a link only answer or not copying someone else's solution)

Create a environment file with a temporary cron entry

* * * * *  /usr/bin/env > /home/username/cron-env

Then create a shell script called run-as-cron which executes the command using that environment.

#!/bin/sh

. "$1"
exec /usr/bin/env -i "$SHELL" -c ". $1; $2"

Give it execute permission

chmod +x run-as-cron

and then it is then used like this:

./run-as-cron <cron-environment> <command>

e.g.

./run-as-cron /home/username/cron-env 'echo $PATH'

Solution 2:[2]

When I want to test my cron jobs I usually set the interval very low and monitor the logs closely. When I am convinced the entry is correct, I set the interval back to a sane value.

For example, run job every two minutes:

*/2 * * * * echo "Hello World"

And the I run tail -f on my log file (/var/log/syslogon debian).

Solution 3:[3]

Joshua's answer does not work for me. Two problems:

  • Variables in cron-env file are not exported (set -a needed).

  • Script is still tied to current tty (setsid needed).

The script run-as-cron should be

#!/bin/sh

. "$1"
exec setsid /usr/bin/env -i "$SHELL" -c "set -a; . $1; $2" </dev/null

Not enough rep' to fix his answer or add a comment...

Solution 4:[4]

use command crontab -e This will open a vim editor and all you got to do here is * * * * * /somepath/urscript.sh , make sure you have the appropriate spaces between dates and the path of the script After the execution , you can check in the /var/spool/mail there will a complete trail of the script execution or errors. For testing there is no way .. but in case ur sh urscript.sh works then cron tab will have no problem as it is exactly same thing what u do manually.

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution Source
Solution 1 Clément
Solution 2 Martin Olsen
Solution 3
Solution 4

Related Questions