If an alarm is configured to require acknowledgment then each raised instance of the alarm remains present in Spotlight until it is acknowledged.
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How to acknowledge an alarm

An alarm can be acknowledged from Spotlight Today or a Spotlight Overview page.

Click Acknowledge Acknowledge.

How to look up an alarm once it has been acknowledged

Locate the alarm in the Alarm log.

The entry in the alarm log grid shows:

Acknowledged by The login name of the user who acknowledged the alarm.
Acknowledgment Comment The comment entered by the user when they acknowledged the alarm.

How to configure an alarm to require acknowledgment

Use the Spotlight Client to configure an alarm to require acknowledgment.

Tags: acknowledge