code: func (ncc *SeesawNCC) BGPAdvertiseVIP(vip net.IP, unused *int) error {
  	bgp, err := quaggaBGP(seesawASN)
  	if err != nil {
  		return err
  	}
  	defer bgp.Close()
  	return bgp.Advertise(&net.IPNet{IP: vip, Mask: hostMask(vip)})
  }
docs: // BGPAdvertiseVIP requests the Quagga BGP daemon to advertise the given VIP.