the alert email was fired,but only onetime I did not receive an alert email.

Question

Even though the alert email created by the alert rule was fired, I did not receive the alert email once. There was no alert email when I searched my junk mail. It has not been suppressed, and I have confirmed that it was foamed. What could be the possible cause?

Answer 1

@kazuki sakai - Thanks for reaching out.

It could be a probable cause that Automatically Resolve alerts may be enabled like the below eg -

Alert state is different and independent of the monitor condition. Alert state is set by the user. Monitor condition is set by the system. When an alert fires, the alert's monitor condition is set to 'fired', and when the underlying condition that caused the alert to fire clears, the monitor condition is set to 'resolved'. The alert state isn't changed until the user changes it.
Learn how to change the state of your alerts and smart groups.

if that is enabled, then try to uncheck the box and issue must be resolved.

Hope this helps.

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