Multi Region Disaster Recovery Questions

Designing systems for resilience and availability across geographic regions, including strategies for cross region replication, failover, and operational recovery. Candidates should understand deployment models such as active active and active passive and the trade offs they imply for availability, consistency, cost, and operational complexity. Discuss replication topologies and the differences between synchronous and asynchronous replication and how those choices affect consistency and the recovery point objective. Cover leader election and failover coordination mechanisms, conflict resolution approaches including last write wins, version vectors, and convergent data types, and implications for transactional guarantees and global transactions. Include global traffic routing and failover techniques such as DNS based routing, global load balancing, health checks, and the impact of routing and time to live on failover behavior. Address data partitioning and cross region latency trade offs, strategies for orchestrating data recovery and region seeding, backup and restore practices, and testing approaches such as planned failovers, rehearsal drills, and chaos testing. Explain how to derive and meet recovery time objective and recovery point objective from business requirements, and consider monitoring, observability, automation, runbooks, cost considerations, and compliance and data residency requirements.