Check_MK Integration

The iLert Check_MK Integration helps you to easily connect iLert with Check_MK.

With the iLert Check_MK notification plugin you can easily integrate Check_MK into iLert and extend your existing Check_MK system with SMS, push and voice notifications as well as on-call schedules from iLert. The screenshots below are based on the Check_MK Raw Edition (CRE) 1.2.8. The iLert Check_MK plugin is compatible with all Check_MK versions.

In iLert: create alert source

1. Create a new alert source in iLert

2. Select the type Nagios / Icinga and click save.

3. An API key is generated. You will need the API conclusions below when setting up the plugin.

In Check_MK: configure iLert Plugin

Download the Check_MK plugin package and unzip it:

> wget
> unzip

For Check_MK you need the two files and You can delete the remaining files in the directory. Move the plugin file into the directory /usr/local/bin . Both files must be executable by both Check_MK and the cron daemon:

> mv /usr/local/bin
> chmod 755 /usr/local/bin/
> chmod 755

Standalone version of Check_MK
OMD version of Check_MK
Standalone version of Check_MK

If you are using the standalone version of Check_MK, follow the instructions below. If you are using the OMD version, please go the tab OMD version of Check_MK.

> crontab -u nagios -e

Add the following entry:

* * * * * /usr/local/bin/ -m send

Via this cron job, events are sent to iLert every minute that failed in the first send attempt (e..g due to a network error).

Move the iLert alerting script to the notifications directory of Check_MK:

> mv /usr/share/check_mk/notifications
OMD version of Check_MK

If you are using the OMD version of Check_MK, follow the instructions below.

> su - {site-name}

Create a file named ilert under the cron.d directory of your monitoring instance (e.g. /omd/sites/{site-name}/etc/cron.d). The file should contain the following content:

* * * * * /usr/local/bin/ -m send

Execute the following command for the changes to take effect:

> omd reload crontab
> exit

Move the iLert alerting script to the notifications directory of Check_MK:

> mv /omd/sites/{site-name}/local/share/check_mk/notifications

Log in to Check_MK's web GUI and continue there.

1. Navigate to the "Users" menu and click on "New User".

2. Fill in the fields marked below. Add the user to the contact groups to which the hosts or services that you want to be alerted for. Click on "Save".

3. Go to the notification settings of this user (by clicking on the "Notifications" icon).

4. Click on "New Rule" and select iLert Check_MK Plugin as the "Notification Method". Enter your iLert API key (see above) as a parameter.

5. Go back to the user list and activate your changes by clicking on "1 Changes":

Test the integration

You can test the integration directly in Check_MK to verify that everything is working. To do this, open a host or service check in the Web GUI and click on the "Execute" icon (Hammer Icon). In "Fake check results" you can manually set the state of a host or service. Click on "Down" (for a host) or "Critical" (for a service) and then confirm with "Yes!". You should now see an incident in iLert.


Which alarm types (Notification Types) are processed by the plugin?

The plugin processes the notification types PROBLEM , ACKNOWLEDGEMENT and RECOVERY. The remaining Notification Types (including FLAPPING* and DOWNTIME*) are ignored.

Check_MK has the following alarm types:




Normal host or service problem


Host / service goes UP / OK again


Acknowledgment of a problem


A host / service begins to be discontinuous


End of discontinuity


Start of scheduled maintenance.


Normal end of maintenance


Premature termination of maintenance


Alarm triggered manually by command


Alerthandler execution (CEE from 1.4.0i2)

What happens if my internet connection is lost? Are the events generated in Check_MK lost?

No, events won't be lost. The plugin stores the events locally in a temporary directory (by default in /tmp/ilert_nagios) and tries to send them to iLert every minute. This means that as soon as your connection is available again, cached events will be sent to iLert. In addition, we recommend that you monitor your Internet connection using our uptime monitoring feature.

Will incidents in iLert be resolved automatically?

Yes, as soon as the state of a host / service is UP or OK again in Check_MK, the associated incident is resolved in iLert. If a problem is acknowledged in Check_MK, the associated incident in iLert is set to the status Accepted.

Can I link Check_MK to multiple alert sources in iLert?

Yes, create a Check_MK user for each alert source in Check_MK. Proceed as described above in the instructions.

The plugin does not work. How do I find the issue?

Please look first in the log file. The plugin uses the Unix / Linux system log for logging (eg under /var/log/messages or /var/log/syslog ). If you can not find the error, please contact our support at .

Please also have a look at the Check_MK documentation, where additional log files related to alerting are documented: The course of a notification from beginning to end