How-to create cronjob inside the Checkmk site

Owned by Anastasios Thomaidis
Last updated: Dec 11, 2023 by Matthew Hierholzer
1 min read
If you want to run a cronjob inside the Checkmk site, please follow this short How-To.

LAST TESTED ON CHECKMK 2.1.0P1

Table of Contents


With crontab -l, you will get an overview of all installed crontabs inside the Checkmk site.

OMD[mysite]:~/etc/check_mk/multisite.d/wato$ crontab -l
#
# Do not edit this file. It will be recreated each time OMD
# is started or reloaded.
#
# execute 'omd reload crontab'
# to rebuild this file out of /omd/sites/mysite/etc/cron.d/*
#
# --ENVIRONMENT------------------------------------------------
SHELL=/bin/bash
BASH_ENV=/omd/sites/mysite/.profile
OMD_ROOT=/omd/sites/mysite
OMD_SITE=mysite
PATH=/omd/sites/mysite/local/bin:/omd/sites/mysite/bin:/usr/local/bin:/bin:/usr/bin:/sbin:/usr/sbin
MAILTO=""
# ------------------------------------------------------------
# /omd/sites/mysite/etc/cron.d/cmk_bulk_notify
# Needed for bulk notifcations.
...
...
...
...


Step-by-step guide

Option #1

  1. create a file below /omd/sites/mysite/etc/cron.d with your new cronjob, e.g. /omd/sites/mysite/etc/cron.d/myjob

    # My cronjob
*/5 * * * * $OMD_ROOT/local/myjob --params >/dev/null 2>&1


  2. execute 'omd reload crontab' to rebuild this file from/omd/sites/mysite/etc/cron.d/*

    root@linux:~# omd reload crontab

Option #2

The second possibility is to create a systemwide cronjob below /etc/cron.d, e.g. /etc/cron.d/myjob. Note the slightly different syntax: the 6th column (after the time settings) requires the user under which this cronjob is executed. Also, the environment variables $OMD_ROOT and such are not available (unless you set them explicitly in this file):