hardMultiple Choice
CAS-004 Practice Question: A cloud security architect is designing a…
A cloud security architect is designing a multi-region active-active application. The application must maintain high availability even if an entire AWS region fails. Which architecture BEST meets this requirement?
⚠ Common exam trap
The primary trap in this question is that candidates may confuse multi-AZ or single-region high availability with true multi-region active-active resilience, or assume that Route 53 health checks alone make an architecture active-active when they are often used for failover (active-passive).
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Deploy identical stacks in two regions with Route 53 weighted routing and DynamoDB global tables
Deploying identical application stacks in two AWS regions with Route 53 weighted routing distributes traffic evenly across both regions, and DynamoDB global tables provide multi-region, multi-master replication with eventual consistency, ensuring the application remains fully active and available even if an entire AWS region fails. This architecture meets the active-active and region-failure requirement without relying on failover or single-region dependencies.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Active-active in one region with auto scaling
Why it's wrong here
Auto scaling within one region cannot survive that region's failure, since all capacity and data reside there. Single-region active-active is the right design when the availability target is zone-level resilience with lowest latency and cost.
- ✓
Deploy identical stacks in two regions with Route 53 weighted routing and DynamoDB global tables
Why this is correct
Identical stacks in two regions with Route 53 weighted routing distribute traffic across regions, while DynamoDB global tables replicate data multi-directionally, so either region can serve writes if the other fails. This satisfies the requirement to survive a complete regional outage.
- ✗
Single region with multiple AZs and RDS Multi-AZ
Why it's wrong here
RDS Multi-AZ replicates synchronously only within one region, so a full regional outage takes the database offline regardless of how many availability zones are used. It is tempting because Multi-AZ genuinely delivers automatic failover for single-region high availability, which would satisfy the requirement had the stem not demanded resilience across an entire region's failure.
- ✗
Two regions with active-passive failover using Route 53 health checks
Why it's wrong here
Active-passive failover keeps one region idle until Route 53 health checks detect failure, so it cannot serve traffic from both regions simultaneously as active-active requires. It is tempting because Route 53 failover routing is the standard pattern for disaster recovery, and would be correct where a warm standby region is acceptable.
Go deeper
Related to this question
About these practice questions
This CAS-005 question is part of Courseiva's 973-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This CAS-005 practice question is part of Courseiva's free CompTIA certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the CAS-005 exam.