1. Notifying via ServiceNow
The connection of ServiceNow is
only available for the Enterprise Editions. The ServiceNow platform allows the mapping and
automation of various workflows (keyword ITIL), including the alerting of users
based on Checkmk notifications.
The integration runs using the instance URL and login data.
2. Configuring ServiceNow
A special configuration within ServiceNow is not required, only the instance URL (possibly in the form of a custom URL) and user data must be known.
3. Configuration in Checkmk
To set up basic alarming in Checkmk, proceed as follows:
For the Notification Method choose the item Servicenow (Enterprise only).
For the Servicenow URL enter your instance URL.
Add the username and password of the creating user.
Under Caller ID add the username of the _ concerned_ user.

All other options are only used to design the alarm content. For the two options unique to ServiceNow, Urgency and Impact, you will find links to the respective entries in the ServiceNow documentation in the Checkmk online help.
For testing you can use the Fake check results and Custom notification commands.