code: func (runner *runner) UpdateVirtualServer(vs *VirtualServer) error {
  	svc, err := toIPVSService(vs)
  	if err != nil {
  		return err
  	}
  	runner.mu.Lock()
  	defer runner.mu.Unlock()
  	return runner.ipvsHandle.UpdateService(svc)
  }
docs: // UpdateVirtualServer is part of ipvs.Interface.