AWS Certified DevOps Engineer – ProfessionalResilient Cloud SolutionsHard
A global e-commerce company operates a highly available web application across multiple AWS Regions. The application uses Amazon EC2 instances in Auto Scaling groups behind Application Load Balancers (ALBs). The company wants to implement a disaster recovery strategy that ensures minimal downtime and data loss in the event of a regional outage. They need to be able to quickly switch all user traffic to a healthy region and restore database functionality without manual intervention. Which disaster recovery strategy should the company implement?
- AMulti-Region Active-Passive (Warm Standby)
- BBackup and Restore with point-in-time recovery
- CPilot Light with manual failover
- DMulti-Region Active-Active (Multi-Site)
Show answer & explanationAnswer & explanation
Correct answer: D. Multi-Region Active-Active (Multi-Site)
For minimal downtime and data loss in a global e-commerce scenario requiring quick, automated failover, an Active-Active (Multi-Site) strategy is superior. This approach keeps resources in multiple regions fully operational and synchronized, allowing for immediate traffic shifting and continuous operation during a regional outage.
Why the other options are wrong
- A. Warm Standby reduces RTO compared to Backup and Restore, but still requires scaling up resources and potentially a manual or semi-automated failover, which doesn't meet the 'minimal downtime' and 'without manual intervention' requirements as effectively as Active-Active.
- B. Backup and Restore involves significant Recovery Time Objective (RTO) and Recovery Point Objective (RPO) as it requires restoring data and launching infrastructure after a disaster.
- C. Pilot Light involves keeping a minimal set of core resources running, but requires significant scaling up and a manual failover process, which does not meet the requirements for minimal downtime and no manual intervention.
Multi-Region Active-Active (Multi-Site)
A disaster recovery strategy where identical, fully operational resources are deployed in multiple AWS Regions and serve traffic concurrently. This provides the highest availability and lowest RTO/RPO.
- All regions actively serve traffic.
- Requires data synchronization across regions.
- Lowest RTO and RPO among DR strategies.
- Highest cost due to duplicate resources.
Memory trick: Always Be Ready, Just In Case, On Demand.