Data residency requirements can constrain where personal or regulated data is stored and processed. A global architecture may need regional databases, regional encryption keys, restricted replication, and carefully controlled telemetry. Confirm legal requirements with qualified stakeholders rather than assuming all data can move freely.

Global routing can use DNS, anycast, or application-layer routing. DNS failover is not instantaneous because of resolver caching and client behavior. Health checks must avoid directing all traffic to a region that is reachable but unable to serve correct requests.

A regional failover plan should define detection, traffic shift, write fencing, data consistency checks, and failback. Failback is often harder than failover because the recovered region may contain stale or divergent data. Run regular game days and measure both recovery objectives and correctness after recovery.