HealthCheckCustomConfig

A complex type that contains information about an optional custom health check. A custom health check, which requires that you use a third-party health checker to evaluate the health of your resources, is useful in the following circumstances:

• You can't use a health check that's defined by HealthCheckConfig because the resource isn't available over the internet. For example, you can use a custom health check when the instance is in an Amazon VPC. (To check the health of resources in a VPC, the health checker must also be in the VPC.)

• You want to use a third-party health checker regardless of where your resources are located.

If you specify a health check configuration, you can specify either HealthCheckCustomConfig or HealthCheckConfig but not both.

To change the status of a custom health check, submit an UpdateInstanceCustomHealthStatus request. Cloud Map doesn't monitor the status of the resource, it just keeps a record of the status specified in the most recent UpdateInstanceCustomHealthStatus request.

Here's how custom health checks work:

• You create a service.

• You register an instance.

• You configure a third-party health checker to monitor the resource that's associated with the new instance. Cloud Map doesn't check the health of the resource directly.

• The third-party health-checker determines that the resource is unhealthy and notifies your application.

• Your application submits an UpdateInstanceCustomHealthStatus request.

• Cloud Map waits for 30 seconds.

• If another UpdateInstanceCustomHealthStatus request doesn't arrive during that time to change the status back to healthy, Cloud Map stops routing traffic to the resource.