Question 1

A mobile application has thousands of users. Each user may use multiple devices to access the application. The Developer wants to assign unique identifiers to these users regardless of the device they use.

Which of the below is the BEST method to obtain unique identifiers?

Options :

A : Implement developer-authenticated identities by using Amazon Cognito and get credentials for these identities

B : Create a user table in Amazon DynamoDB with key-value pairs of users and their devices. Use these keys as unique identifiers

C : Use IAM-generated access key IDs for the users as the unique identifier, but do not store secret keys

D : Assign IAM users and roles to the users. Use the unique IAM resource ID as the unique identifier

Answer: A

Question 2

A company recently deployed a new serverless user portal. Users have reported that part of the portal is slow. The initial analysis found a single Amazon API Gateway endpoint that is responsible for the performance issues. The endpoint integrates with an AWS Lambda function. However, the Lambda function interacts with other APIs and AWS services.

How can a developer find the source of the increased response time by using operational best practices?

Options :

A : Update the Lambda function by adding logging statements with high-precision timestamps before and after each external request. Deploy the updated Lambda function. After accumulating enough usage data, examine the Amazon CloudWatch logs for the Lambda function to determine the likely sources for the increased response time.

B : Instrument the Lambda function with the AWS X-Ray SDK. Add HTTP and HTTPS interceptors and SDK client handlers. Deploy the updated Lambda function. Turn on X-Ray tracing. After accumulating enough usage data, use the X-Ray service map to examine the average response times to determine the likely sources.

C : Review the Lambda function-s Amazon CloudWatch metrics by using the metrics explorer. Apply anomaly detection to the Duration metric and the Throttles metric. Review the anomalies to determine the likely sources.

D : Use Amazon CloudWatch Synthetics to create a new canary. Turn on AWS X-Ray tracing on the canary. Configure the canary to scan the user portal. After accumulating enough usage data, use the CloudWatch Synthetics canary dashboard to view the metrics from the canary.

Answer: B

Question 3

There are multiple AWS accounts across multiple regions managed by a company. The operations team require a single operational dashboard that displays some key performance metrics from these accounts and regions. What is the SIMPLEST solution?

Options :

A : Create an Amazon CloudWatch dashboard in one account and region and import the data from the other accounts and regions

B : Create an AWS Lambda function that collects metrics from each account and region and pushes the metrics to the account where the dashboard has been created

C : Create an Amazon CloudTrail trail that applies to all regions and deliver the logs to a single Amazon S3 bucket. Create a dashboard using the data in the bucket

D : Create an Amazon CloudWatch cross-account cross-region dashboard

Answer: D

Question 4

A developer maintains a critical business application that uses Amazon DynamoDB as the primary data store The DynamoDB table contains millions of documents and receives 30-60 requests each minute The developer needs to perform processing in near-real time on the documents when they are added or updated in the DynamoDB table How can the developer implement this feature with the LEAST amount of change to the existing application code?

Options :

A :

Set up a cron job on an Amazon EC2 instance Run a script every hour to query the table for changes and process the documents

B :

Enable a DynamoDB stream on the table Invoke an AWS Lambda function to process the documents.

C :

Update the application to send a PutEvents request to Amazon EventBridge. Create an EventBridge rule to invoke an AWS Lambda function to process the documents.

D :

Update the application to synchronously process the documents directly after the DynamoDB write

Answer: B

Question 5

A developer has created an Amazon API Gateway with caching enabled in front of AWS Lambda. For some requests, it is necessary to ensure the latest data is received from the endpoint. How can the developer ensure the data is not stale?

Options :

A : The cache must be disabled

B : Modify the TTL on the cache to a lower number

C : Send requests with the Cache-Control: max-age=0 header

D : Send requests with the Cache-Delete: max-age=0 header

Answer: C