func (opsgenie *OpsGenieNotifier) closeAlert(alertCli *ogcli.OpsGenieAlertClient, alias string) bool {
	log.Debug(fmt.Sprintf("OpsGenieAlertClient.CloseAlert alias: %s", alias))
	req := alerts.CloseAlertRequest{
		Alias:  alias,
		Source: "consul",
	}
	response, alertErr := alertCli.Close(req)

	if alertErr != nil {
		if response == nil {
			log.Warn("Opsgenie notification trouble. ", alertErr)
		} else {
			log.Warn("Opsgenie notification trouble. ", response.Status)
		}
		return false
	}

	log.Println("Opsgenie close alert sent.")
	return true
}