Failover routing for disaster recovery in AWS - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Understanding Failover Routing Behavior

In AWS Route 53, failover routing is used to route traffic to a primary resource and switch to a secondary resource if the primary becomes unhealthy.

What happens when the health check for the primary resource fails?

A Route 53 stops routing traffic to both primary and secondary resources until manual intervention.

B Traffic continues to be routed to the primary resource regardless of health check status.

C Traffic is automatically routed to the secondary resource configured in the failover routing policy.

D Traffic is routed randomly between primary and secondary resources.

💡 Hint

Think about what failover means in disaster recovery.

Failover routing automatically directs traffic to the secondary resource when the primary fails health checks, ensuring availability.

❓ Configuration

intermediate

Configuring Health Checks for Failover Routing

You want to configure failover routing in AWS Route 53 to switch traffic to a backup server if the primary server is down.

Which of the following is a required step to enable failover routing?

A Configure a weighted routing policy instead of failover routing.

B Create a health check for the secondary resource only.

C Disable health checks and rely on DNS TTL for failover.

D Create a health check for the primary resource and associate it with the primary record set.

💡 Hint

Failover routing depends on health checks to detect failures.

Failover routing requires a health check on the primary resource to detect when it is unhealthy and trigger failover.

❓ Architecture

advanced

Designing a Multi-Region Failover Architecture

You are designing a disaster recovery solution using AWS Route 53 failover routing between two regions.

Which architecture best supports automatic failover with minimal downtime?

A Primary region hosts the application with a health check; secondary region is standby with identical setup and DNS failover configured.

B Both regions serve traffic simultaneously with weighted routing and no health checks.

C Secondary region hosts the application; primary region is used only for backups.

D Primary region only, with manual DNS update to secondary region during failure.

💡 Hint

Failover routing requires health checks and a standby resource ready to serve traffic.

Automatic failover requires a primary region with health checks and a secondary region ready to take over, configured in Route 53 failover routing.

❓ security

advanced

Security Considerations in Failover Routing

When implementing failover routing for disaster recovery, which security practice is most important to protect DNS failover configurations?

A Restrict Route 53 console access using IAM policies to authorized personnel only.

B Use public IP addresses only for all resources to simplify routing.

C Disable health checks to prevent false failover triggers.

D Allow all users to modify DNS records for faster recovery.

💡 Hint

Think about who should control DNS settings in a disaster recovery setup.

Restricting access to Route 53 configurations prevents unauthorized changes that could disrupt failover routing and cause downtime.

❓ service_behavior

expert

Analyzing Failover Routing Behavior with Health Check Flapping

In AWS Route 53 failover routing, if the primary resource's health check status rapidly changes between healthy and unhealthy (flapping), what is the expected behavior?

A Route 53 immediately switches traffic to secondary resource on any unhealthy status without delay.

B Route 53 uses a configurable evaluation period to stabilize health check status before switching traffic, preventing rapid failover toggling.

C Route 53 disables failover routing until manual reset is performed.

D Route 53 routes traffic to both primary and secondary resources simultaneously during flapping.

💡 Hint

Consider how health checks are evaluated over time to avoid instability.

Route 53 health checks have evaluation intervals and thresholds to avoid rapid failover toggling caused by transient failures.