diff --git a/pkg/stub/stub.go b/pkg/stub/stub.go
index 3cc837b0..c3b886d3 100644
--- a/pkg/stub/stub.go
+++ b/pkg/stub/stub.go
@@ -137,7 +137,9 @@ type PostUpdateContainerInterface interface {
 
 // Stub is the interface the stub provides for the plugin implementation.
 type Stub interface {
-	// Run the plugin. Starts the plugin then waits for an error or the plugin to stop
+	// Run starts the plugin then waits for the plugin service to exit, either due to a
+	// critical error or an explicit call to Stop(). Once Run() returns, the plugin can be
+	// restarted by calling Run() or Start() again.
 	Run(context.Context) error
 	// Start the plugin.
 	Start(context.Context) error
@@ -255,7 +257,6 @@ type stub struct {
 	rpcs       *ttrpc.Server
 	rpcc       *ttrpc.Client
 	runtime    api.RuntimeService
-	closeOnce  sync.Once
 	started    bool
 	doneC      chan struct{}
 	srvErrC    chan error
@@ -288,7 +289,6 @@ func New(p interface{}, opts ...Option) (Stub, error) {
 		idx:        os.Getenv(api.PluginIdxEnvVar),
 		socketPath: api.DefaultSocketPath,
 		dialer:     func(p string) (stdnet.Conn, error) { return stdnet.Dial("unix", p) },
-		doneC:      make(chan struct{}),
 	}
 
 	for _, o := range opts {
@@ -316,10 +316,10 @@ func (stub *stub) Start(ctx context.Context) (retErr error) {
 	stub.Lock()
 	defer stub.Unlock()
 
-	if stub.started {
+	if stub.isStarted() {
 		return fmt.Errorf("stub already started")
 	}
-	stub.started = true
+	stub.doneC = make(chan struct{})
 
 	err := stub.connect()
 	if err != nil {
@@ -401,6 +401,7 @@ func (stub *stub) Start(ctx context.Context) (retErr error) {
 
 	log.Infof(ctx, "Started plugin %s...", stub.Name())
 
+	stub.started = true
 	return nil
 }
 
@@ -413,24 +414,42 @@ func (stub *stub) Stop() {
 	stub.close()
 }
 
+// IsStarted returns true if the plugin has been started either by Start() or by Run().
+func (stub *stub) IsStarted() bool {
+	stub.Lock()
+	defer stub.Unlock()
+	return stub.isStarted()
+}
+
+func (stub *stub) isStarted() bool {
+	return stub.started
+}
+
+// reset stub to the status that can initiate a new
+// NRI connection, the caller must hold lock.
 func (stub *stub) close() {
-	stub.closeOnce.Do(func() {
-		if stub.rpcl != nil {
-			stub.rpcl.Close()
-		}
-		if stub.rpcs != nil {
-			stub.rpcs.Close()
-		}
-		if stub.rpcc != nil {
-			stub.rpcc.Close()
-		}
-		if stub.rpcm != nil {
-			stub.rpcm.Close()
-		}
-		if stub.srvErrC != nil {
-			<-stub.doneC
-		}
-	})
+	if !stub.isStarted() {
+		return
+	}
+
+	if stub.rpcl != nil {
+		stub.rpcl.Close()
+	}
+	if stub.rpcs != nil {
+		stub.rpcs.Close()
+	}
+	if stub.rpcc != nil {
+		stub.rpcc.Close()
+	}
+	if stub.rpcm != nil {
+		stub.rpcm.Close()
+	}
+	if stub.srvErrC != nil {
+		<-stub.doneC
+	}
+
+	stub.started = false
+	stub.conn = nil
 }
 
 // Run the plugin. Start event processing then wait for an error or getting stopped.
@@ -449,14 +468,11 @@ func (stub *stub) Run(ctx context.Context) error {
 	return err
 }
 
-// Wait for the plugin to stop.
+// Wait for the plugin to stop, should be called after Start() or Run().
 func (stub *stub) Wait() {
-	stub.Lock()
-	if stub.srvErrC == nil {
-		return
+	if stub.IsStarted() {
+		<-stub.doneC
 	}
-	stub.Unlock()
-	<-stub.doneC
 }
 
 // Name returns the full indexed name of the plugin.
@@ -518,7 +534,9 @@ func (stub *stub) register(ctx context.Context) error {
 
 // Handle a lost connection.
 func (stub *stub) connClosed() {
+	stub.Lock()
 	stub.close()
+	stub.Unlock()
 	if stub.onClose != nil {
 		stub.onClose()
 		return