// Otherwise there are multiple destination clusters and destination host is not clear. For that case
	// return virtual service name:port/uri as substitute.
	if c := in.GetRoute().GetCluster(); model.IsValidSubsetKey(c) {
		// Parse host and port from cluster name.
		_, _, h, p := model.ParseSubsetKey(c)
		return string(h) + ":" + strconv.Itoa(p) + path
	}
	return vsName + ":" + strconv.Itoa(port) + path
}