While describing the Range behavior, slide notes state:
A zero value triggers and clears the alarm at the threshold point that you configured.Room for improvement:
This statement is unclear and could be better worded. Also, it is not true that a zero value will clear the alarm immediately after triggering it.Correct:
The following phrase could be a better description of the above concept:
A zero value means that the alarm triggers whenever the metric value is above or below the specified value.Source:
vSphere 5.1 Documentation Center.