Question 1

A Development team currently supports an application that uses an in-memory store to save accumulated game results. Individual results are stored in a database. As part of migrating to AWS, the team needs to use automatic scaling. The team knows this will yield inconsistent results. Where should the team store these accumulated game results to BEST allow for consistent results without impacting performance?

Accepted Answer

Amazon ElastiCache is an in-memory data store that supports automatic scaling and provides consistent performance, making it suitable for storing accumulated game results.

Question 2

A Developer has created a Lambda function and is finding that the function is taking longer to complete than expected. After some debugging, the Developer has discovered that increasing compute capacity would improve performance. How can the Developer increase the Lambda compute resources?

Accepted Answer

The answer of A Developer has created a Lambda function...

Question 3

A company has an application that logs all information to Amazon S3. Whenever there is a new log file, an AWS Lambda function is invoked to process the log files. The code works, gathering all of the necessary information. However, when checking the Lambda function logs, duplicate entries with the same request ID are found. What is causing the duplicate entries?

Accepted Answer

AWS Lambda functions can be invoked multiple times with the same request ID if the function fails or times out. The Lambda service automatically retries the invocation, which can lead to duplicate processing of the same event.

Question 4

A company is using Amazon RDS MySQL instances for its application database tier and Apache Tomcat servers for its web tier. Most of the database queries from web applications are repeated read requests. Use of which AWS service would increase in performance by adding in-memory store for repeated read queries?

Accepted Answer

The answer of A company is using Amazon RDS MySQL...

Question 5

A company is providing services to many downstream consumers. Each consumer may connect to one or more services. This has resulted in a complex architecture that is difficult to manage and does not scale well. The company needs a single interface to manage these services to consumers. Which AWS service should be used to refactor this architecture?

Accepted Answer

Amazon API Gateway provides a single entry point for managing multiple services, allowing the company to simplify its architecture and improve scalability by routing requests to the appropriate services.

Question 6

A company uses Amazon DynamoDB for managing and tracking orders. The DynamoDB table is partitioned based on the order date. The company receives a huge increase in orders during a sales event, causing DynamoDB writes to throttle, and the consumed throughput is far below the provisioned throughput. According to AWS best practices, how can this issue be resolved with MINIMAL costs?

Accepted Answer

The answer of A company uses Amazon DynamoDB for managing...

Question 7

A Developer is building a mobile application and needs any update to user profile data to be pushed to all devices accessing the specific identity. The Developer does not want to manage a back end to maintain the user profile data. What is the MOST efficient way for the Developer to achieve these requirements using Amazon Cognito?

Accepted Answer

The answer of A Developer is building a mobile application...

Question 8

A company maintains a REST service using Amazon API Gateway and the API Gateway native API key validation. The company recently launched a new registration page, which allows users to sign up for the service. The registration page creates a new API key using CreateApiKey and sends the new key to the user. When the user attempts to call the API using this key, the user receives a 403 Forbidden error. Existing users are unaffected and can still call the API. What code updates will grant these new users access to the API?

Accepted Answer

The importApiKeys method must be called to import all newly created API keys into the current stage of the API.

Question 9

A Developer is making changes to a custom application that is currently using AWS Elastic Beanstalk. After the Developer completes the changes, what solutions will update the Elastic Beanstalk environment with the new application version? (Choose two.)

Accepted Answer

The answer of A Developer is making changes to a...

Question 10

A Developer is designing a new application that uses Amazon S3. To satisfy compliance requirements, the Developer must encrypt the data at rest. How can the Developer accomplish this?

Accepted Answer

Enabling S3 default encryption ensures that all objects stored in the bucket are automatically encrypted at rest, satisfying compliance requirements.

Question 11

A Developer has a stateful web server on-premises that is being migrated to AWS. The Developer must have greater elasticity in the new design. How should the Developer re-factor the application to make it more elastic? (Choose two.)

Accepted Answer

The answer of A Developer has a stateful web server...

Question 12

A Developer is creating an AWS Lambda function to process a stream of data from an Amazon Kinesis Data Stream. When the Lambda function parses the data and encounters a missing field, it exits the function with an error. The function is generating duplicate records from the Kinesis stream. When the Developer looks at the stream output without the Lambda function, there are no duplicate records. What is the reason for the duplicates?

Accepted Answer

When the Lambda function encounters an error and exits without advancing the Kinesis stream pointer, it causes the same record to be reprocessed, leading to duplicate records.

Question 13

An application that runs on an Amazon EC2 instance needs to access and make API calls to multiple AWS services. What is the MOST secure way to provide access to the AWS services with MINIMAL management overhead?

Accepted Answer

The answer of An application that runs on an Amazon...

Question 14

A Developer has published an update to an application that is served to a global user base using Amazon CloudFront. After deploying the application, users are not able to see the updated changes. How can the Developer resolve this issue?

Accepted Answer

The answer of A Developer has published an update to...

Question 15

A company is migrating a single-server, on-premises web application to AWS. The company intends to use multiple servers behind an Elastic Load Balancer (ELB) to balance the load, and will also store session data in memory on the web server. The company does not want to lose that session data if a server fails or goes offline, and it wants to minimize user's downtime. Where should the company move session data to MOST effectively reduce downtime and make users' session data more fault tolerant?

Accepted Answer

Using Amazon ElastiCache for Redis allows session data to be stored in-memory across multiple nodes, providing high availability and fault tolerance. This minimizes downtime and ensures session data is not lost if a web server fails.

Question 16

A Developer must analyze performance issues with production-distributed applications written as AWS Lambda functions. These distributed Lambda applications invoke other components that make up the applications. How should the Developer identify and troubleshoot the root cause of the performance issues in production?

Accepted Answer

AWS X-Ray is designed for analyzing and debugging distributed applications, such as those using AWS Lambda. It helps trace requests and visualize the application architecture, making it easier to identify performance bottlenecks and errors.

Question 17

A company has a multi-tiered web application on AWS. During a recent spike in traffic, one of the primary relational databases on Amazon RDS could not serve all the traffic. Some read queries for repeatedly accessed items failed, so users received error messages. What can be done to minimize the impact on database read queries MOST efficiently during future traffic spikes?

Accepted Answer

The answer of A company has a multi-tiered web application...

Question 18

A Developer wants access to make the log data of an application running on an EC2 instance available to systems administrators. Which of the following enables monitoring of this metric in Amazon CloudWatch?

Accepted Answer

The Amazon CloudWatch Logs agent needs to be installed on the EC2 instance to collect and send log data to CloudWatch for monitoring.

Question 19

A company is running an application built on AWS Lambda functions. One Lambda function has performance issues when it has to download a 50MB file from the Internet in every execution. This function is called multiple times a second. What solution would give the BEST performance increase?

Accepted Answer

The answer of A company is running an application built...

Question 20

A Developer created configuration specifications for an AWS Elastic Beanstalk application in a file named healthcheckurl.yaml in the .ebextensions/directory of their application source bundle. The file contains the following:  After the application launches, the health check is not being run on the correct path, even though it is valid. What can be done to correct this configuration file?

Accepted Answer

The answer of A Developer created configuration specifications for an...

Exam 6: AWS Certified Developer Associate (DVA-C01)