diff --git a/app/firenze/cmd/firenze b/app/firenze/cmd/firenze
deleted file mode 100755
index 606dbb89..00000000
Binary files a/app/firenze/cmd/firenze and /dev/null differ
diff --git a/library/melody/hub.go b/library/melody/hub.go
index 293b095a..e017e7c5 100644
--- a/library/melody/hub.go
+++ b/library/melody/hub.go
@@ -108,6 +108,10 @@ func (h *hub) len() int {
 }
 
 func (h *hub) all() []*Session {
+	if h == nil {
+		return nil
+	}
+
 	h.rwmutex.RLock()
 	defer h.rwmutex.RUnlock()
 
@@ -118,7 +122,29 @@ func (h *hub) all() []*Session {
 	return s
 }
 
+func (h *hub) GetDidSession(did string) *Session {
+	if h == nil {
+		return nil
+	}
+	if len(did) <= 0 {
+		return nil
+	}
+
+	h.rwmutex.RLock()
+	s := h.didSessionMap[did]
+	h.rwmutex.RUnlock()
+
+	return s
+}
+
 func (h *hub) updateSession(s *Session) {
+	if h == nil {
+		return
+	}
+	if s == nil {
+		return
+	}
+
 	if len(s.Sid) > 0 {
 		h.rwmutex.Lock()
 		h.sidSessionMap[s.Sid] = s
diff --git a/library/melody/melody.go b/library/melody/melody.go
index d0adb5d2..a5fa0be0 100644
--- a/library/melody/melody.go
+++ b/library/melody/melody.go
@@ -202,6 +202,13 @@ func (m *Melody) HandleRequestWithKeys(w http.ResponseWriter, r *http.Request, k
 		baseReq.Did = baseReq.Channel
 	}
 
+	// 检查设备
+	oldSession := m.hub.GetDidSession(baseReq.Did)
+	if oldSession != nil {
+		logger.Warn("device reconnect: %d - %s", baseReq.Mid, baseReq.Did)
+		oldSession.close()
+	}
+
 	// 升级协议
 	conn, err := m.Upgrader.Upgrade(w, r, w.Header())
 	if err != nil {