What happens if the alert didn't fire as you expected or you didn't get an email notification? Here are some troubleshooting tips that might help you diagnose the problem.
Checking the alert history
The first step is to checkState history. Located next to the Test Rule button, the State history button opens a pane with the current state (which you can clear if it gets too long). The state history displays the current state and up to 49 additional previous states. It might be the case that the alert has triggered but is still in a pending state, for example. Here's what a typical state history looks like:
Checking the history is a good way of getting an idea of how often your rules are firing and whether you have configured them to correctly transition from state to state, especially if you expect your alerts to switch back to OK when an alerting condition has reverted for...