A company is using a cloud-based CRM system to manage customer interactions. They need to ensure that their customer data is continuously available, even in the event of a regional outage or disaster affecting a single data center. The recovery time objective (RTO) is near zero, and the recovery point objective (RPO) is also near zero. Which data replication strategy would best meet these stringent requirements?
- ASynchronous replication across multiple regions
- BActive-active replication across multiple regions
- CSnapshot-based replication to a separate availability zone
- DAsynchronous replication to a secondary region
Show answer & explanationAnswer & explanation
Correct answer: B. Active-active replication across multiple regions
Active-active replication across multiple regions provides the highest availability and disaster recovery capabilities, allowing for near-zero RTO and RPO by having multiple instances of the application and data simultaneously active and synchronized in different regions. This ensures continuous operation even during a regional outage.
Why the other options are wrong
- A. Synchronous replication across multiple regions typically incurs high latency and performance overhead, often impractical for large-scale applications with near-zero RPO/RTO requirements over long distances.
- C. Snapshot-based replication results in a significant RPO (data loss since last snapshot) and RTO (time to restore from snapshot).
- D. Asynchronous replication introduces some data loss (non-zero RPO) and recovery time (non-zero RTO).
Active-Active Replication
Active-active replication is a high-availability and disaster recovery strategy where multiple instances of an application and its underlying data are simultaneously running and processing requests across different geographical regions or data centers, ensuring continuous operation with near-zero RTO and RPO.
- All instances are live and serving traffic.
- Data is synchronized in real-time across instances.
- Provides near-zero RTO and RPO.
- Complex to implement and manage consistency.
Memory trick: Active-Active: Always On, Always Ready.