Multi-Region Traffic Routing

Active-active.

Overview

Multi-region traffic routing distributes user traffic across regions for resilience, latency, or compliance. Active-active is the modern default; active-passive remains valid where regions are too coupled to run live concurrently. The discipline is producing predictable cross-region behaviour under failure.

• Active-active capacity. Both regions serve traffic; doubles capacity ceiling and removes the cold-standby tax that active-passive carries.
• Latency-based routing. Users get the nearest healthy region; Route 53 latency policies, GCP global LB, Azure Traffic Manager all support this natively.
• Health checks. Regional health checks remove unhealthy regions from rotation; produces automatic regional failover without on-call intervention.
• Failover policies and compliance routing. Active-passive is the alternative; data residency requirements may force regional routing regardless of resilience preference.

The approach

Global DNS plus regional health checks plus deliberate failover testing. The team's discipline produces predictable behaviour under failure rather than discovering the routing model during the incident.

• Global DNS. Route 53, Cloud DNS, or Azure DNS provides global resolution; use managed DNS rather than rolling your own anycast.
• Latency-based default. Most users get the nearest region; produces low latency without manual routing rules per user.
• Regional health checks. External monitors validate each region; unhealthy regions are removed from DNS rotation automatically.
• Test the failover. Game-day exercises validate the routing; configuration drift surfaces during drills rather than during incidents.

Why this compounds

Multi-region routing compounds across regions added: each new region inherits the patterns, team confidence in failover grows, and the system stops treating regional failure as an outage.

• Reduced regional incident impact. Regional failure becomes a routing event, not a customer-facing outage; the resilience pays back every regional failure thereafter.
• Better global latency. Users globally get fast service from the nearest region; latency improvements compound across every request.
• Compliance flexibility. Regional routing supports data residency; opens markets that single-region deployments cannot serve.
• Team confidence. Each tested failover increases on-call confidence; failover moves from theoretical to operational.

Multi-region traffic routing is one of those infrastructure investments that pays off across years. Nova AI Ops integrates with regional telemetry, surfaces routing patterns, and supports the team's resilience discipline.