Question #769
A solutions architect must design a reference architecture for a three-tier application with web, application, and relational database layers on AWS. The architecture must meet the following requirements:
- High availability within a single AWS Region
- Disaster recovery failover to another AWS Region within 1 minute
- Cost efficiency while minimizing user experience degradation
Which combination of steps will meet these requirements? (Choose three.)
Use Amazon Route 53 weighted routing policy configured as 100/0 between the primary and disaster recovery Regions. Set Time to Live (TTL) to 1 hour.
Configure Amazon Route 53 with a failover routing policy for primary-to-disaster recovery Region routing. Set TTL to 30 seconds.
Deploy an Amazon Aurora Global Database with read replicas in both Regions to enable low-latency cross-Region data access.
Schedule hourly snapshots of the Amazon RDS database in the primary Region and replicate them to Amazon S3. Use S3 cross-Region replication to the disaster recovery Region. Restore from snapshots during failover.
Implement a warm standby model using Auto Scaling groups for web/application tiers across Availability Zones. Use Reserved Instances for baseline capacity and On-Demand Instances for scaling.
Use Auto Scaling groups with Spot Instances for web/application layers across multiple Availability Zones.
Explanation
B (Route 53 failover routing with 30s TTL) ensures DNS updates propagate quickly, meeting the 1-minute failover requirement. C (Aurora Global Database) provides low-latency replication and fast promotion in DR scenarios. E (warm standby with Reserved/On-Demand) minimizes costs while maintaining readiness.
A's 1-hour TTL delays failover. D's hourly snapshots result in data loss and slow recovery. F's Spot Instances risk availability. Key points: Use Route 53 failover policies with low TTL, Aurora Global Database for cross-Region DB replication, and warm standby with Reserved Instances for cost efficiency.
Answer
The correct answer is: BCE