When using IBM IoT Real-Time insights, we can define alerts that trigger when an event arrives that passes some rule condition. This can trigger an action such as sending an email. Is there a technique that will allow us to generate an alert the first time that a condition is true but will not generate an alert for subsequent events until the condition first evaluates to false?
Imagine I am receiving temperature events from a pipeline sensor. When the temperature passes 120oF, I want to receive an alert ... however it appears to me that the temperature event value will continue to be above this threshold temperature for each subsequent event which will result in the condition evaluating true many times. If the action I want to have performed is to email me, then I believe I will receive a new email for each new event received which isn't what I am wanting. What I really want to happen is to receive an email the first time the temperature passes a threshold and no more until the problem is corrected and it may happen again.
The continuous triggering of alerts once a rule threshold is met is a limitation that is currently being addressed by the IoT Real-Time Insights team. Keep an eye on the What's new in Bluemix section for news about new features as they are released.