Question 1

During non-peak hours, a Developer wants to minimize the execution time of a full Amazon DynamoDB table scan without affecting normal workloads. The workloads average half of the strongly consistent read capacity units during non-peak hours. How would the Developer optimize this scan?

Accepted Answer

A)  Use parallel scans while limiting the rate 
B)  Use sequential scans 
C)  Increase read capacity units during the scan operation 
D)  Change consistency to eventually consistent during the scan operation

Question 2

A Developer needs to create an application that supports Security Assertion Markup Language (SAML) and Facebook authentication. It must also allow access to AWS services, such as Amazon DynamoDB. Which AWS service or feature will meet these requirements with the LEAST amount of additional coding?

Accepted Answer

A)  AWS AppSync 
B)  Amazon Cognito identity pools 
C)  Amazon Cognito user pools 
D)  Amazon Lambda@Edge

Question 3

A developer is trying to get data from an Amazon DynamoDB table called demoman-table. The developer configured the AWS CLI to use a specific IAM user's credentials and executed the following command:  The command returned errors and no rows were returned. What is the MOST likely cause of these issues?

Accepted Answer

A)  The command is incorrect; it should be rewritten to use put-item with a string argument. The command is incorrect; it should be rewritten to use put-item with a string argument. 
B)  The developer needs to log a ticket with AWS Support to enable access to the demoman-table. 
C)  Amazon DynamoDB cannot be accessed from the AWS CLI and needs to be called via the REST API. 
D)  The IAM user needs an associated policy with read access to demoman-table.

Question 4

When uploading an object, what request header can be explicitly specified in a request to Amazon S3 to encrypt object data when saved on the server side?

Accepted Answer

A)  x-amz-storage-class 
B)  Content-MD5 
C)  x-amz-security-token 
D)  x-amz-server-side-encryption

Question 5

What type of block cipher does Amazon S3 offer for server side encryption?

Accepted Answer

A)  Triple DES 
B)  Advanced Encryption Standard 
C)  Blowfish 
D)  RC5

Question 6

A Developer has discovered that an application responsible for processing messages in an Amazon SQS queue is routinely falling behind. The application is capable of processing multiple messages in one execution, but is only receiving one message at a time. What should the Developer do to increase the number of messages the application receives?

Accepted Answer

A)  Call the ChangeMessageVisibility API for the queue and set MaxNumberOfMessages to a value greater than the default of 1. 
B)  Call the AddPermission API to set MaxNumberOfMessages for the ReceiveMessage action to a value greater than the default of 1. 
C)  Call the ReceiveMessage API to set MaxNumberOfMessages to a value greater than the default of 1. 
D)  Call the SetQueueAttributes API for the queue and set MaxNumberOfMessages to a value greater than the default of 1.

Question 7

A developer is building a new application that uses an Amazon DynamoDB table. The specification states that all items that are older than 48 hours must be removed. Which solution will meet this requirement?

Accepted Answer

A)  Create a new attribute that has the Number data type. Add a local secondary index (LSI) for this attribute, and enable TTL with an expiration of 48 hours. In the application code, set the value of this attribute to the current timestamp for each new item that is being inserted. 
B)  Create a new attribute that has the String data type. Add a local secondary index (LSI) for this attribute, and enable TTL with an expiration of 48 hours. In the application code, set the value of this attribute to the current timestamp for each new item that is being inserted. 
C)  Create a new attribute that has the Number data type. Enable TTL on the DynamoDB table for this attribute. In the application code, set the value of this attribute to the current timestamp plus 48 hours for each new item that is being inserted. 
D)  Create a new attribute that has the String data type. Enable TTL on the DynamoDB table for this attribute. In the application code, set the value of this attribute to the current timestamp plus 48 hours for each new item that is being inserted.

Question 8

Company B provides an online image recognition service and utilizes SQS to decouple system components for scalability The SQS consumers poll the imaging queue as often as possible to keep end-to-end throughput as high as possible. However, Company B is realizing that polling in tight loops is burning CPU cycles and increasing costs with empty responses. How can Company B reduce the number of empty responses?

Accepted Answer

A)  Set the imaging queue visibility Timeout attribute to 20 seconds 
B)  Set the Imaging queue ReceiveMessageWaitTimeSeconds attribute to 20 seconds 
C)  Set the imaging queue MessageRetentionPeriod attribute to 20 seconds 
D)  Set the DelaySeconds parameter of a message to 20 seconds

Question 9

When a Simple Queue Service message triggers a task that takes 5 minutes to complete, which process below will result in successful processing of the message and remove it from the queue while minimizing the chances of duplicate processing?

Accepted Answer

A)  Retrieve the message with an increased visibility timeout, process the message, delete the message from the queue 
B)  Retrieve the message with an increased visibility timeout, delete the message from the queue, process the message 
C)  Retrieve the message with increased DelaySeconds, process the message, delete the message from the queue 
D)  Retrieve the message with increased DelaySeconds, delete the message from the queue, process the message

Question 10

An organization is storing large files in Amazon S3, and is writing a web application to display meta-data about the files to end-users. Based on the metadata a user selects an object to download. The organization needs a mechanism to index the files and provide single-digit millisecond latency retrieval for the metadata. What AWS service should be used to accomplish this?

Accepted Answer

A)  Amazon DynamoDB 
B)  Amazon EC2 
C)  AWS Lambda 
D)  Amazon RDS

Question 11

An organization is using Amazon API Gateway to provide a public API called "Survey" for collecting user feedback posts about its products. The survey API has "DEV" and "PROD" stages and consists of one resource " /feedback " which allows users to retrieve/create/update single feedback posts. A version-controlled Swagger file is used to define a new API that retrieves multiple feedback posts. To add the new API resource " /listFeedbackForProduct " the developer makes changes to the Swagger file defining an API, uploads the file to the organization's version control system, and uses the API Gateway Import API feature to apply the changes to the Survey API. After successful import, the developer runs the tests against the DEV stage and finds that resource " " is not available. What is MOST likely the reason for resource not being available?

Accepted Answer

A)  Even though the Swagger import was successful, resource creation failed afterwards. 
B)  There is a propagation delay of several minutes in creating API Gateway resources after import. 
C)  The developer needs to restart the API Gateway stage after import in order to apply the changes. 
D)  The developer needs to create a new deployment after import in order to deploy the changes.

Question 12

A meteorological system monitors 600 temperature gauges, obtaining temperature samples every minute and saving each sample to a DynamoDB table. Each sample involves writing 1K of data and the writes are evenly distributed over time. How much write throughput is required for the target table?

Accepted Answer

A)  1 write capacity unit 
B)  10 write capacity units 
C)  60 write capacity units 
D)  600 write capacity units 
E)  3600 write capacity units

Question 13

A company has an AWS CloudFormation template that is stored as a single file. The template is able to launch and create a full infrastructure stack. Which best practice would increase the maintainability of the template?

Accepted Answer

A)  Use nested stacks for common template patterns. 
B)  Embed credentials to prevent typos. 
C)  Remove mappings to decrease the number of variables. 
D)  Use AWS::Include to reference publicly-hosted template files. Use AWS::Include to reference publicly-hosted template files.

Question 14

A Developer has created a new AWS IAM user that has s3 putObject permission to write to a specific Amazon S3 bucket. This S3 bucket uses server-side encryption with AWS KMS managed (SSE-KMS) as the default encryption. Using the access key and secret key of the IAM user, the application received an access denied error when calling the PutObject API. How can this issue be resolved?

Accepted Answer

A)  Update the policy of the IAM user to allow the s3 Encrypt action. 
B)  Update the bucket policy of the S3 bucket to allow the IAM user to upload objects. 
C)  Update the policy of the IAM user to allow the kms:GenerateDataKey action. 
D)  Update the ACL of the S3 bucket to allow the IAM user to upload objects.

Question 15

An Amazon DynamoDB table uses a Global Secondary Index (GSI) to support read queries. The primary table is write-heavy, whereas the GSI is used for read operations. Looking at Amazon CloudWatch metrics, the Developer notices that write operations to the primary table are throttled frequently under heavy write activity. However, write capacity units to the primary table are available and not fully consumed. Why is the table being throttled?

Accepted Answer

A)  The GSI write capacity units are underprovisioned 
B)  There are not enough read capacity units on the primary table 
C)  Amazon DynamoDB Streams is not enabled on the table 
D)  A large write operation is being performed against another table

Question 16

A developer is monitoring an application running on an Amazon EC2 instance. The developer has configured a custom Amazon CloudWatch metric with data granularity of 1 second. If there are any issues, the developer wants to be notified within 30 seconds using Amazon Simple Notification Service (Amazon SNS). Which CloudWatch mechanism will satisfy this requirement?

Accepted Answer

A)  Configure a high-resolution CloudWatch alarm. 
B)  Set up a custom CloudWatch dashboard. 
C)  Use Amazon CloudWatch Logs Insights. 
D)  Change to a default CloudWatch metric.

Question 17

A developer is implementing authentication and authorization for an application. The developer needs to ensure that the user credentials are never exposed. Which approach should the developer take to meet this requirement?

Accepted Answer

A)  Store the user credentials in Amazon DynamoDB. Build an AWS Lambda function to validate the credentials and authorize users. 
B)  Deploy a custom authentication and authorization API on an Amazon EC2 instance. Store the user credentials in Amazon S3 and encrypt the credentials using Amazon S3 server-side encryption. 
C)  Use Amazon Cognito to configure a user pool, and user the Cognito API to authenticate and authorize the user. 
D)  Store the user credentials in Amazon RDS. Enable the encryption option for the Amazon RDS DB instances. Build an API using AWS Lambda to validate the credentials and authorize users.

Question 18

A company is launching an ecommerce website and will host the static data in Amazon S3. The company expects approximately 1,000 transactions per second (TPS) for GET and PUT requests in total. Logging must be enabled to track all requests and must be retained for auditing purposes. What is the MOST cost-effective solution?

Accepted Answer

A)  Enable AWS CloudTrail logging for the S3 bucket-level action and create a lifecycle policy to move the data from the log bucket to Amazon S3 Glacier in 90 days. 
B)  Enable S3 server access logging and create a lifecycle policy to expire the data in 90 days. 
C)  Enable AWS CloudTrail logging for the S3 bucket-level action and create a lifecycle policy to expire the data in 90 days. 
D)  Enable S3 server access logging and create a lifecycle policy to move the data to Amazon S3 Glacier in 90 days.

Question 19

A software company needs to make sure user-uploaded documents are securely stored in Amazon S3. The documents must be encrypted at rest in Amazon S3. The company does not want to manage the security infrastructure in-house, but the company still needs extra protection to ensure it has control over its encryption keys due to industry regulations. Which encryption strategy should a Developer use to meet these requirements?

Accepted Answer

A)  Server-side encryption with Amazon S3 managed keys (SSE-S3) 
B)  Server-side encryption with customer-provided encryption keys (SSE-
C)  
C)  Server-side encryption with AWS KMS managed keys (SSE-KMS) 
D)  Client-side encryption

Question 20

How can a developer use a debugger for AWS Lambda code that is deployed with AWS Serverless Application Model (AWS SAM)?

Accepted Answer

A)  Download the Lambda code locally and use the AWS CLI to execute it 
B)  Use the Lambda console to connect the debugger 
C)  Use AWS SAM to invoke a function locally in debug mode 
D)  Connect a third-party-compatible integrated development environment (ID
E)  to the Lambda debugger endpoint

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