Route 53 Failover practice questions

A company is designing a new multi-region disaster recovery solution for a critical application running on AWS. The primary region is us-east-1. The application uses Amazon RDS for MySQL with Multi-AZ, and runs on EC2 instances behind an ALB. The RPO must be less than 5 minutes, and RTO less than 30 minutes. The company wants to minimize costs when the DR solution is not in use. Which solution should a Solutions Architect recommend?

Trap 1: Use RDS MySQL with cross-Region read replicas in us-west-2

A single EC2 instance is a single point of failure; read replicas are for read scaling, not automatic failover.

Trap 2: Back up RDS MySQL to S3 using automated snapshots and copy them to…

Snapshot backup RPO can be up to 24 hours; restoring from S3 is slow, RTO will exceed 30 minutes.

Trap 3: Use RDS MySQL with Multi-AZ in us-east-1 and a second Multi-AZ…

Multi-AZ is within a region; cross-Region load balancing is not a native feature; keeping instances running incurs cost.

A
Use RDS MySQL with cross-Region read replicas in us-west-2. Use a hot standby EC2 environment with a single instance. Use Route 53 failover routing.
Why wrong: A single EC2 instance is a single point of failure; read replicas are for read scaling, not automatic failover.
B
Back up RDS MySQL to S3 using automated snapshots and copy them to us-west-2. Use EC2 instances with S3-mounted volumes to serve traffic from the backup.
Why wrong: Snapshot backup RPO can be up to 24 hours; restoring from S3 is slow, RTO will exceed 30 minutes.
C
Use RDS MySQL with Multi-AZ in us-east-1 and a second Multi-AZ deployment in us-west-2. Keep EC2 instances running in us-west-2 behind an ALB with cross-Region load balancing.
Why wrong: Multi-AZ is within a region; cross-Region load balancing is not a native feature; keeping instances running incurs cost.
D
Set up an RDS MySQL cross-Region read replica in us-west-2. Keep a standby EC2 environment with Auto Scaling configured to scale from 0 to minimum instances using a CloudWatch alarm on health checks. Use Route 53 failover routing to switch DNS to us-west-2.
Cross-Region read replicas provide low RPO; scaling from 0 minimizes cost; Route 53 failover provides RTO.

Question 2mediummultiple choice

A company is migrating a web application to AWS. The application uses a three-tier architecture with a web server, application server, and MySQL database. The company wants to ensure high availability by deploying across multiple Availability Zones. The web and application servers are stateless. Which solution provides the HIGHEST availability with the LEAST administrative effort?

Trap 1: Deploy web and application servers on EC2 instances in an Auto…

Single AZ is a single point of failure; cross-region adds complexity and latency.

Trap 2: Deploy web, application, and database on a single large EC2…

Single AZ does not provide high availability; snapshot recovery takes time.

Trap 3: Deploy web and application servers on EC2 instances in two AZs with…

Elastic IPs are not highly available; manual intervention needed for failover.

A
Deploy web and application servers on EC2 instances in an Auto Scaling group across two AZs with an Application Load Balancer. Use Multi-AZ Amazon RDS for MySQL.
ALB and Auto Scaling provide automatic scaling and failover; Multi-AZ RDS provides database failover.
B
Deploy web and application servers on EC2 instances in an Auto Scaling group in one AZ. Use Amazon Route 53 latency-based routing to another region.
Why wrong: Single AZ is a single point of failure; cross-region adds complexity and latency.
C
Deploy web, application, and database on a single large EC2 instance in one AZ. Take snapshots every hour.
Why wrong: Single AZ does not provide high availability; snapshot recovery takes time.
D
Deploy web and application servers on EC2 instances in two AZs with Elastic IP addresses. Use Amazon Route 53 with health checks to route traffic.
Why wrong: Elastic IPs are not highly available; manual intervention needed for failover.

Question 3hardmultiple choice

A company is designing a multi-region active-active application using Amazon Route 53 latency-based routing. The application runs on Amazon EC2 instances behind Application Load Balancers (ALBs) in two AWS Regions. The company needs to ensure that if one region becomes unavailable, traffic is automatically routed to the healthy region with minimal disruption. Which configuration meets these requirements?

Trap 1: Use Route 53 failover routing instead of latency-based routing.

Failover routing is for active-passive, not active-active.

Trap 2: Configure Route 53 latency-based routing without health checks.

Without health checks, Route 53 will still send traffic to unhealthy endpoints.

Trap 3: Use Route 53 weighted routing with weights set to 50 for each…

Weighted routing does not automatically failover based on health.

A
Use Route 53 failover routing instead of latency-based routing.
Why wrong: Failover routing is for active-passive, not active-active.
B
Configure Route 53 latency-based routing without health checks.
Why wrong: Without health checks, Route 53 will still send traffic to unhealthy endpoints.
C
Use Route 53 weighted routing with weights set to 50 for each region.
Why wrong: Weighted routing does not automatically failover based on health.
D
Configure Route 53 latency-based routing with health checks attached to each ALB endpoint.
Health checks allow Route 53 to automatically route traffic away from unhealthy endpoints.

Question 4easymultiple choice

A company is designing a new application that will run on Amazon EC2 instances behind an Application Load Balancer. The application needs to store session state. Which AWS service provides a fully managed, highly scalable solution for session state management?

Trap 1: Amazon DynamoDB

DynamoDB is a NoSQL key-value and document database, not a session state management service; it lacks built-in session replication, expiry, and locking mechanisms that a dedicated service like ElastiCache for Redis provides. It is tempting because its low-latency performance and fully managed scaling make it ideal for storing session data in a custom implementation, and it would be correct if the question asked for a durable, serverless database for session persistence rather than a managed caching layer.

Trap 2: Amazon S3

S3 is object storage and not designed for low-latency session state access.

Trap 3: Amazon RDS for MySQL

RDS is a relational database, which adds latency and overhead compared to in-memory caching.

A
Amazon DynamoDB
Why wrong: DynamoDB is a NoSQL key-value and document database, not a session state management service; it lacks built-in session replication, expiry, and locking mechanisms that a dedicated service like ElastiCache for Redis provides. It is tempting because its low-latency performance and fully managed scaling make it ideal for storing session data in a custom implementation, and it would be correct if the question asked for a durable, serverless database for session persistence rather than a managed caching layer.
B
Amazon ElastiCache for Redis
ElastiCache for Redis is a fully managed, highly scalable, in-memory data store ideal for session state.
C
Amazon S3
Why wrong: S3 is object storage and not designed for low-latency session state access.
D
Amazon RDS for MySQL
Why wrong: RDS is a relational database, which adds latency and overhead compared to in-memory caching.

Question 5mediummultiple choice

A company is designing a multi-region disaster recovery solution for a stateless web application running on Amazon ECS Fargate. The application uses an Application Load Balancer and stores session data in Amazon ElastiCache for Redis. The company needs to achieve an RPO of 15 minutes and an RTO of 30 minutes. What is the MOST cost-effective design that meets these requirements?

Trap 1: Deploy a second ECS cluster and ALB in the secondary region with no…

Scaling up tasks from zero will exceed RTO.

Trap 2: Use a multi-region ECS service with Service Connect and Route 53…

Active-active is more expensive than needed for RTO 30 min.

Trap 3: Use pilot light by replicating ECS task definitions and copying…

Snapshot restore RPO is too high; pilot light not best for stateless app.

A
Deploy a second ECS cluster and ALB in the secondary region with no tasks. Use cross-Region replication for ElastiCache. Use Route 53 to fail over after scaling up tasks.
Why wrong: Scaling up tasks from zero will exceed RTO.
B
Deploy a second ECS cluster and ALB in the secondary region with a scaled-down number of tasks. Use ElastiCache Global Datastore for Redis to replicate session data. Use Route 53 health checks to fail over.
Correct: Warm standby with Global Datastore meets RPO and RTO.
C
Use a multi-region ECS service with Service Connect and Route 53 latency-based routing. Keep equal capacity in both regions.
Why wrong: Active-active is more expensive than needed for RTO 30 min.
D
Use pilot light by replicating ECS task definitions and copying AMIs to the secondary region. Use ElastiCache snapshot and restore. Fail over with Route 53.
Why wrong: Snapshot restore RPO is too high; pilot light not best for stateless app.

Question 6easymultiple choice

A company is designing a new web application that will be accessed by users worldwide. The application should have low latency and high availability. The application uses a stateless web tier and a relational database. Which architecture minimizes latency for global users?

Trap 1: Deploy the application in a single region and use Route 53…

Geolocation still routes to a single region; latency is not minimized globally.

Trap 2: Deploy the application in multiple regions, use CloudFront to cache…

This is partially correct but doesn't address the database latency.

Trap 3: Deploy the application in a single region and use Amazon CloudFront…

Dynamic content still needs to travel to the origin region, increasing latency.

A
Deploy the application in multiple regions with Route 53 latency-based routing, and use Amazon Aurora Global Database for the database tier.
Aurora Global Database allows reads from local regions, reducing latency for read-heavy workloads.
B
Deploy the application in a single region and use Route 53 geolocation routing.
Why wrong: Geolocation still routes to a single region; latency is not minimized globally.
C
Deploy the application in multiple regions, use CloudFront to cache static content, and route dynamic requests to the nearest region via Route 53 latency-based routing.
Why wrong: This is partially correct but doesn't address the database latency.
D
Deploy the application in a single region and use Amazon CloudFront to cache content globally.
Why wrong: Dynamic content still needs to travel to the origin region, increasing latency.

Question 7easymultiple choice

A company uses AWS CodePipeline to deploy a web application. They want to automatically roll back the deployment if the new version fails CloudWatch alarm-based health checks. Which feature should they use?

Trap 1: AWS Lambda function invoked by CloudWatch Events.

Lambda could be used, but CodeDeploy has built-in rollback based on alarms.

Trap 2: Amazon Route 53 health checks with failover routing.

Route 53 health checks are for DNS-level failover, not deployment rollback.

Trap 3: AWS CodeBuild with post-build actions.

CodeBuild is for building and testing, not deployment rollback.

A
AWS Lambda function invoked by CloudWatch Events.
Why wrong: Lambda could be used, but CodeDeploy has built-in rollback based on alarms.
B
Amazon Route 53 health checks with failover routing.
Why wrong: Route 53 health checks are for DNS-level failover, not deployment rollback.
C
AWS CodeBuild with post-build actions.
Why wrong: CodeBuild is for building and testing, not deployment rollback.
D
CodeDeploy automatic rollback configuration with CloudWatch alarm.
CodeDeploy supports automatic rollback when a CloudWatch alarm is in ALARM state.

Question 8mediummulti select

A company is designing a disaster recovery solution for a critical application that runs on Amazon EC2 instances in a single AWS Region. The application uses an Amazon RDS for MySQL database. The recovery time objective (RTO) is 1 hour and the recovery point objective (RPO) is 15 minutes. Which combination of steps should the company take to meet these requirements? (Choose THREE.)

Trap 1: Configure a Multi-AZ deployment for the RDS database in the primary…

Multi-AZ is for high availability within a Region, not for cross-Region DR.

Trap 2: Deploy the application on Amazon Aurora Global Database.

Aurora is a different database engine, not RDS MySQL.

A
Use Amazon Route 53 health checks to monitor the primary application and configure DNS failover to the secondary Region.
Route 53 health checks and failover route traffic to the secondary Region when the primary fails.
B
Configure a Multi-AZ deployment for the RDS database in the primary Region.
Why wrong: Multi-AZ is for high availability within a Region, not for cross-Region DR.
C
Deploy the application on Amazon Aurora Global Database.
Why wrong: Aurora is a different database engine, not RDS MySQL.
D
Create an Amazon Machine Image (AMI) of the EC2 instances and copy it to the secondary Region. Use an Auto Scaling group to launch instances from the AMI.
Copying AMIs to another Region allows recovery of EC2 instances.
E
Create a cross-Region read replica of the RDS MySQL database in the secondary Region.
Cross-Region read replicas provide asynchronous replication with low RPO.