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Running a cron job randomly for every one hour

I want a cronjob to run every one hour randomly. (i.e if the first job runs at 58 minutes,the second job should run at 47 minutes and the third one at 52 minutes and so on) But this should run randomly for everyone hour. Is there a way to do this?

Solution

  • You could run a job every hour, on the hour, that sleeps up to 3,599 seconds and then executes your script:

    0 * * * * /bin/bash -c 'sleep $((RANDOM%3600))' && /path/to/yourScript

    Or, with Perl:

    0 * * * * /path/to/perl -e 'sleep int rand 3600' && /path/to/yourScript

    Or, using PHP if you prefer that to Perl:

    0 * * * * /path/to/php -r 'sleep(rand(0,3599));' && /path/to/yourScript

    You can find the path to Perl with:

    which perl

    likewise for PHP:

    which php