Event transformations allow us to alter an event's properties with a Python expression. For example, we can use an event transformation to:
Suppress, drop, or otherwise alter the state of an event.
Assign the event properties, such as severity, state, or summary, based on a conditional check of another device or event.
Process events by location.
Sort the incoming syslog messages for further handling.
... and much, much more
Event transformations are a flexible tool in your Zenoss Core toolbox, and how you use them will largely depend on your imagination, needs, and scripting abilities.
Zenoss Core is a Python-based application and as a result, knowing Python will drastically increase what you can do with event transformations. However, for the non-Python people among us, myself included, we can still use the event transformations to do some things. Appendix A, Event Attributes and Appendix B, Device Attributes contain event and device attributes that you can use in your transformations...