You have configured an Alarm Definition in the Oracle Cloud Infrastructure (OCI) Monitoring service to send notifications through email. The alarm…

In Oracle Cloud Infrastructure Monitoring, an alarm evaluates metric data against a specified threshold. By default, when an alarm transitions from an OK state to a FIRING state, the Monitoring service sends a single notification to the designated topic via OCI Notifications. If the metric condition continues to breach the threshold and remains continuously in the FIRING state, additional periodic notifications are not sent unless repeat notifications are explicitly configured. Enabling repeat notifications allows users to specify an interval duration for resending alert messages while the alarm remains active. Thus, the subscriber's issue is caused by not enabling repeat notifications during alarm creation.

Option A: OCI Monitoring supports sending continuous repeat notifications for firing alarms if the repeat notification setting is explicitly configured in the alarm definition.
Option C: Trigger conditions define when an alarm fires; without a trigger condition, the alarm cannot evaluate metrics or fire in the first place.
Option D: Notification repetition is governed strictly by the repeat notification setting duration, not by the total quantity of metric streams returned.

- Oracle Cloud Infrastructure Documentation, "Managing Alarms - Repeat Notifications", Monitoring Guide, Section: Alarm Options and Repeat Notifications, 2024.

- Oracle Cloud Infrastructure Documentation, "Alarm Definitions and Notifications Syntax", Monitoring Concepts, 2024.