AWS Certified Developer Associate · Free Practice Question Medium
Question 47
A Developer is creating an application that uses Amazon EC2 instances and must be highly available and fault tolerant. How should the Developer configure the VPC?
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A
Create a cluster placement group for the EC2 instances
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B
Create a subnet in each availability zone in the region
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C
Create an Internet Gateway for every availability zone
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D
Create multiple subnets within a single availability zone in the region
Reveal correct answer
Correct answer: B
Explanation
To ensure high availability and fault tolerance the Developer should create a subnet within each availability zone. The EC2 instances should then be distributed between these subnets.
The Developer would likely use Amazon EC2 Auto Scaling which will automatically launch instances in each subnet and then Elastic Load Balancing to distributed incoming traffic.
CORRECT: "Create a subnet in each availability zone in the region" is the correct answer.
INCORRECT: "Create multiple subnets within a single availability zone in the region" is incorrect as this will not provide fault tolerance in the event that the AZ becomes unavailable.
INCORRECT: "Create an Internet Gateway for every availability zone" is incorrect as there is a single Internet Gateway per VPC.
INCORRECT: "Create a cluster placement group for the EC2 instances" is incorrect as this is used for ensuring low latency access between EC2 instances in a single availability zone.
References:
https://d1.awsstatic.com/whitepapers/aws-building-fault-tolerant-applications.pdf
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Discussion
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