startZonalShift
You start a zonal shift to temporarily move load balancer traffic away from an Availability Zone in an Amazon Web Services Region, to help your application recover immediately, for example, from a developer's bad code deployment or from an Amazon Web Services infrastructure failure in a single Availability Zone. You can start a zonal shift in Route 53 ARC only for managed resources in your Amazon Web Services account in an Amazon Web Services Region. Resources are automatically registered with Route 53 ARC by Amazon Web Services services.
At this time, you can only start a zonal shift for Network Load Balancers and Application Load Balancers with cross-zone load balancing turned off.
When you start a zonal shift, traffic for the resource is no longer routed to the Availability Zone. The zonal shift is created immediately in Route 53 ARC. However, it can take a short time, typically up to a few minutes, for existing, in-progress connections in the Availability Zone to complete.
For more information, see Zonal shift in the Amazon Route 53 Application Recovery Controller Developer Guide.