opEvents is really flexible and configurable. In the above schema you can see all the involved files to configure opEvents.
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Once the event is created, EventActions.nmis file specifies how to react to events. The file consist in a set of rules with flexibility to being adapted to a wide variety of use cases.
This file can be edited used the opEvents editor, http://host/en/omk/opEvents/config/actions:
One of the available actions is to notify using email, and different templates can be defined in EventEmails.nmis file.