Hi,
In this case it might be better to disable Automatically resolve alerts (auto mitigate feature). Description for the feature: "Select to make the alert stateful. When an alert is stateful, the alert is resolved when the condition is no longer met.
If you don't select this checkbox, metric alerts are stateless. Stateless alerts fire each time the condition is met, even if alert already fired.
The frequency of notifications for stateless metric alerts differs based on the alert rule's configured frequency:
Alert frequency of less than 5 minutes: While the condition continues to be met, a notification is sent somewhere between one and six minutes.
Alert frequency of more than 5 minutes: While the condition continues to be met, a notification is sent between the configured frequency and double the frequency. For example, for an alert rule with a frequency of 15 minutes, a notification is sent somewhere between 15 to 30 minutes."
That way you will receive notification every time the threshold is met.
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