Answer: Create Amazon CloudWatch composite alarms where possible.

## Explanation **Correct Answer: A - Create Amazon CloudWatch composite alarms where possible.** ### Why this is correct: 1. **Composite alarms** allow you to combine multiple metric alarms using logical operators (AND, OR, NOT). This is exactly what's needed in this scenario. 2. The requirement states that action is needed only when **BOTH** conditions are true simultaneously: - CPU utilization > 50% - Read IOPS are high 3. A single composite alarm can monitor both metrics and trigger only when both conditions are met, which reduces false alarms. 4. Composite alarms can be configured with the AND operator to ensure both conditions must be true before triggering. ### Why other options are incorrect: **B. Create Amazon CloudWatch dashboards to visualize the metrics and react to issues quickly.** - Dashboards are for visualization only and don't provide automated alerting or alarm functionality. - They require manual intervention to detect issues, which doesn't meet the requirement for automated action. **C. Create Amazon CloudWatch Synthetics canaries to monitor the application and raise an alarm.** - Synthetics canaries are for monitoring application endpoints and APIs, not infrastructure metrics like CPU utilization and disk IOPS. - They simulate user traffic and check for application-level issues, not infrastructure-level metrics. **D. Create single Amazon CloudWatch metric alarms with multiple metric thresholds where possible.** - Single metric alarms can only monitor one metric at a time. - While you can set multiple thresholds on a single metric (like CPU > 50% for 5 minutes), you cannot combine different metrics (CPU and IOPS) in a single alarm. - This would require separate alarms for each metric, which could trigger false alarms when only one condition is met. ### Key AWS Concepts: - **Composite Alarms**: Monitor the state of multiple other alarms and trigger based on logical combinations. - **Metric Alarms**: Monitor a single metric and trigger based on thresholds. - **Reducing False Alarms**: Composite alarms help reduce false positives by requiring multiple conditions to be met before triggering. This solution meets all requirements: monitoring both CPU utilization and disk IOPS, triggering only when both conditions are met simultaneously, and reducing false alarms.

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