
Explanation:
Box 1: A Traffic Manager profile
To support load balancing across the regions we need a Traffic Manager.
Box 2: Priority traffic routing
Priority traffic-routing method.
Often an organization wants to provide reliability for their services. To do so, they deploy one or more backup services in case their primary goes down. The 'Priority' traffic-routing method allows Azure customers to easily implement this failover pattern.
Reference:
https://docs.microsoft.com/en-us/azure/architecture/reference-architectures/app-service-web- app/multi-region
https://docs.microsoft.com/en-us/azure/traffic-manager/traffic-manager-routing-methods