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Custom metrics may be useful to make more ad-hoc configuration of autoscaling in AWS. Metric created - ActiveConnectionCount per Healthy Hosts - may be helpful to scale-in-in an application that may stop to respond to health-checks if it is fully loaded. In such a manner, creating different Alarms, it is possible to configure very flexible policies. In general, this metric may be used both to rapidly react on spikes and to take into account the health state of hosts for concurrency based metrics.