Hybrid applications use resources both on premises and in AWS. Users sometimes report the apps are unavailable. A CloudWatch alarm already monitors the Site-to-Site VPN tunnel status. The Ops team needs high-priority tickets created automatically in an internal ticketing system when the VPN tunnel goes down. Which design meets this need?

The correct option leverages Amazon SNS for its ability to fan out notifications. CloudWatch alarms can directly publish to an SNS topic. The internal ticketing system can then subscribe to this SNS topic, receiving notifications when the VPN tunnel goes down and automatically creating a high-priority ticket. This is a common and efficient pattern for integrating AWS monitoring with external systems. Incorrect options: An SQS queue is primarily for decoupling and buffering messages, not directly for transforming and posting to an external ticketing system in this scenario. While an SQS queue could be part of a more complex solution, it's not the most direct or efficient primary target for a CloudWatch alarm to trigger external ticket creation. While a Lambda function could be invoked by the CloudWatch alarm to create tickets, using SNS as an intermediary provides greater flexibility. SNS allows multiple subscribers and simplifies management if other systems also need to be notified in the future, without modifying the alarm itself. Amazon EventBridge can monitor various AWS events, but CloudWatch alarms are already the established mechanism for detecting metric thresholds like VPN tunnel status. An EventBridge rule would be redundant for this specific monitoring task and doesn't offer a more direct integration with the ticketing system than SNS for this use case.