I'm new to Kamailio. I am using Kamailio/dispatcher to distribute calls to several SIP IVRs. I'm trying to determine the best solution to autoscale in AWS when call capacity of the IVRs is reached.

The most straight forward solution is to spin up a new IVR on a dedicated subnet when required. I would configure dispatcher such that the whole IP range of this subnet is in the dispatcher.list so that once a new instance becomes available, Kamailio starts sending calls there.

My question is, how much overhead would this add as Kamailio/dispatcher would be polling the IPs in the subnet that were not yet active. The plan would be to have a /28 subnet with 16 IPs. To start, there would be 2 active IVRs up and responding and 14 IPs in dispatcher.list that would not be responding.