} else {
		if a.cfg.UseExternalWorkloadSDS {
			return nil, errors.New("workload SDS socket is required but not found")
		}
		log.Info("Workload SDS socket not found. Starting Istio SDS Server")
		err = a.initSdsServer()
		if err != nil {
			return nil, fmt.Errorf("failed to start SDS server: %v", err)
		}
	}
	a.xdsProxy, err = initXdsProxy(a)
	if err != nil {
		return nil, fmt.Errorf("failed to start xds proxy: %v", err)

// This should be called before exiting.
func (s *Server) WaitUntilCompletion() {
	s.server.Wait()
}

// initSDSServer starts the SDS server
func (s *Server) initSDSServer() {
	if s.kubeClient == nil {
		return
	}
	if !features.EnableXDSIdentityCheck {
		// Make sure we have security