AWS Certified Devops Engineer Professional · Free Practice Question Hard
Question 7
A DevOps engineer must implement a serverless service that uses Amazon API Gateway, AWS Lambda, and DynamoDB. The serverless service must be deployed in multiple Regions and ensure fast response times for users within each geography.
Which solution will meet the requirements?
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A
Create API Gateway APIs in two Regions and configure Amazon Route 53 with a failover routing policy and health checks. Configure the APIs with a Lambda proxy integration to a function in the same Region. Retrieve and update the data in a DynamoDB global table.
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B
Create API Gateway APIs in each Region and configure Amazon Route 53 with latency-based routing rules and health checks. Configure the APIs with a Lambda proxy integration to a function in the same Region. Retrieve and update the data in a DynamoDB global table.
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C
Create API Gateway APIs in each Region and configure Amazon Route 53 with health checks for each API. Configure the APIs with a Lambda proxy integration to a function in the same Region. Configure the Lambda functions to retrieve and update the data in a DynamoDB table in the same Region as the Lambda function.
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D
Create API Gateway APIs in each Region and configure Amazon Route 53 with latency-based routing rules and health checks. Configure the APIs with a Lambda proxy integration to a central function in one AWS account. Configure the Lambda function to retrieve and update the data in a DynamoDB table in the same Region as the Lambda function.
Reveal correct answer
Correct answer: B
Explanation
The best available solution is to deploy APIs into multiple Regions and configure each API with a local Lambda function as an integration. Users can be directed to the closest API by configuring Amazon Route 53 with latency-based routing rules. The data should be stored in a Global Table, so it is synchronized across Regions. This solution ensures a single data set using the multi-master Global Tables technology and low latency for users.
CORRECT: "Create API Gateway APIs in each Region and configure Amazon Route 53 with latency-based routing rules and health checks. Configure the APIs with a Lambda proxy integration to a function in the same Region. Retrieve and update the data in a DynamoDB global table" is the correct answer (as explained above.)
INCORRECT: "Create API Gateway APIs in each Region and configure Amazon Route 53 with health checks for each API. Configure the APIs with a Lambda proxy integration to a function in the same Region. Configure the Lambda functions to retrieve and update the data in a DynamoDB table in the same Region as the Lambda function" is incorrect.
The issue with this question is there are multiple records in Route 53 for each API but no way to direct users to the best one. A latency-based routing policy would be the best solution for this requirement.
INCORRECT: "Create API Gateway APIs in two Regions and configure Amazon Route 53 with a failover routing policy and health checks. Configure the APIs with a Lambda proxy integration to a function in the same Region. Retrieve and update the data in a DynamoDB global table" is incorrect.
Failover routing works when you have an active and passive deployment. In this case we want an active-active deployment with the serverless service available to users in multiple Regions.
INCORRECT: "Create API Gateway APIs in each Region and configure Amazon Route 53 with latency-based routing rules and health checks. Configure the APIs with a Lambda proxy integration to a central function in one AWS account. Configure the Lambda function to retrieve and update the data in a DynamoDB table in the same Region as the Lambda function" is incorrect.
You cannot configure the APIs with a central Lambda function. You must choose a Lambda function in the same Region as the API.
References:
https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/routing-policy.html
https://aws.amazon.com/dynamodb/global-tables/
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Discussion
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