Routing control components - Amazon Route 53 Application Recovery Controller
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Routing control components

The following diagram illustrates an example of components that support the routing control feature in Route 53 ARC. The routing controls shown here (grouped into one control panel) let you manage traffic to two Availability Zones in each of two Regions. When you update routing control states, Route 53 ARC changes health checks in Amazon Route 53, which redirect DNS traffic to different cells. Safety rules that you configure for routing controls help avoid fail-open scenarios and other unintentional consequences.

Components that support routing control in Route 53 ARC

The following are components of the routing control feature in Route 53 ARC.

Cluster

A cluster is a set of five redundant Regional endpoints against which you initiate API calls to update or get routing control states. A cluster includes a default control panel, and you can host multiple control panels and routing controls on one cluster.

Routing controls

A routing control is a simple on/off switch, hosted on a cluster, that you use to control routing of client traffic in and out of cells. When you create a routing control, you add a Route 53 ARC health check in Route 53. This enables you to reroute traffic (using the health checks, configured with DNS records for your applications) when you update the routing control state in Route 53 ARC.

Routing control health check

Routing controls are integrated with health checks in Route 53. The health checks are associated with DNS records that front each application replica, for example, failover records. When you change routing control states, Route 53 ARC updates the corresponding health checks, which redirect traffic—for example, to failover to your standby replica.

Control panel

A control panel groups together a set of related routing controls. You can associate multiple routing controls with one control panel, and then create safety rules for the control panel to ensure that the traffic redirection updates that you make are safe. For example, you can configure a routing control for each of your load balancers in each Availability Zone, and then group them in the same control panel. Then you can add a safety rule (an "assertion rule") that makes sure that at least one zone (represented by a routing control) is active at any one time, to avoid unintended "fail-open" scenarios.

Default control panel

When you create a cluster, Route 53 ARC creates a default control panel. By default, all routing controls that you create on the cluster are added to the default control panel. Or, you can create your own control panels to group related routing controls.

Safety rule

Safety rules are rules that you add to routing control to ensure that recovery actions don't accidentally impair your application's availability. For example, you can create a safety rule that creates a routing control that acts as an overall "on/off" switch so that you can enable or disable a set of other routing controls.

Endpoint (cluster endpoint)

Each cluster in Route 53 ARC has five Regional endpoints that you can use for setting and retrieving routing control states. Your process for accessing the endpoints should assume that Route 53 ARC regularly brings the endpoints up and down for maintenance, so you should try each endpoint in succession until you connect to one. You access the endpoints to get the current state of routing controls (On or Off) and to trigger failovers for your applications by changing routing control states.