Amazon Web Services Updated SOA-C03 Exam Questions and Answers by ralphie

The CloudWatch agent supports modular configuration using the append-config option, which allows additional log sources to be added without overwriting the existing baseline configuration. This makes it ideal for incremental log collection changes across large fleets.

By creating a separate configuration file specifically for DHCP logs and using Systems Manager Run Command, the CloudOps engineer can remotely update only the relevant instances in a scalable and automated manner. This approach avoids manual login and preserves the existing baseline configuration.

Options B and C require manual intervention on each instance, which is not scalable or operationally efficient. Option D captures additional logs indiscriminately and does not specifically target DHCP logs, potentially increasing noise and cost.

Therefore, Option A is the most efficient and AWS-recommended approach.

Comprehensive and Detailed Explanation From Exact Extract of AWS CloudOps Doocuments:

Use Amazon S3 Event Notifications with AWS Lambda to trigger image processing on object creation. S3 natively supports invoking Lambda for events such as s3:ObjectCreated:*, providing a serverless, low-latency pipeline without managing additional services. AWS operational guidance states that “Amazon S3 can directly invoke a Lambda function in response to object-created events,” allowing you to pass event metadata (bucket/key) to the function for resizing and writing results back to S3. This approach minimizes operational overhead, scales automatically with upload volume, and integrates with standard retry semantics. SNS or SQS can be added for fan-out or buffering patterns, but they are not required when the requirement is simply “invoke the Lambda function on upload.” CloudWatch alarms do not detect individual S3 object uploads and cannot directly satisfy per-object triggers. Therefore, configuring S3 → Lambda event notifications meets the requirement most directly and aligns with CloudOps best practices for event-driven, serverless automation.

Comprehensive and Detailed Explanation From Exact Extract of AWS CloudOps Doocuments:

VPC Flow Logs show the request arriving and being ACCEPTed on dstport 8080 and the corresponding response being REJECTed on the return path to the client’s ephemeral port (59003). AWS networking guidance states that security groups are stateful (return traffic is automatically allowed) while network ACLs are stateless and require explicit inbound and outbound rules for both directions. CloudOps operational guidance for VPC networking further notes that when you allow an inbound request (for example, TCP 8080) through a subnet’s network ACL, you must also allow the outbound ephemeral port range (typically 1024–65535) for the response traffic; otherwise, the return packets are dropped and appear as REJECT in flow logs. The observed pattern—request accepted to 8080, response rejected to 59003—matches a missing outbound ephemeral-range allow on the subnet’s NACL. Therefore, the cause is the subnet NACL, not security groups or on-premises ACLs. The remediation is to add an outbound ALLOW rule on the NACL for the appropriate ephemeral TCP port range back to the on-premises CIDR (and the corresponding inbound rule if asymmetric).

Comprehensive and Detailed Explanation From Exact Extract of AWS CloudOps Documents:

To meet the requirement to log and audit any principal that publishes to SNS topics and interacts with SQS queues, the correct service is AWS CloudTrail, because CloudTrail records API activity (who did what, when, and from where). Enabling data events (where supported/required for deeper visibility) provides detailed records for operations such as publishing messages and sending/receiving messages. Delivering CloudTrail logs to Amazon S3 provides durable retention and supports querying workflows.

To ensure that communication uses VPC endpoints, the company should configure VPC endpoints for SNS and SQS and then validate usage by inspecting CloudTrail event records. CloudTrail includes endpoint-related context fields (for example, a VPC endpoint identifier) that allow auditors to confirm that the request path used a VPC endpoint rather than traversing the public internet. This directly addresses the “must use VPC endpoints” control with auditable evidence.

The other options do not satisfy both requirements. CloudWatch Logs does not automatically capture SNS/SQS API caller identity for publish/send/receive operations in the same authoritative way CloudTrail does. EventBridge can capture service events but is not the primary audit log of API calls and does not inherently prove VPC endpoint usage per request. Inspecting a VPC endpoint field in CloudWatch Logs is not the standard audit mechanism for these API calls.