diff --git a/dpark/pymesos/scheduler.py b/dpark/pymesos/scheduler.py
index <HASH>..<HASH> 100644
--- a/dpark/pymesos/scheduler.py
+++ b/dpark/pymesos/scheduler.py
@@ -59,6 +59,7 @@ class MesosSchedulerDriver(Process):
     @async # called by detector
     def onNewMasterDetectedMessage(self, pid):
         self.master = UPID(pid)
+        self.connected = False
         self.register()
 
     @async # called by detector
fix re-register to master after failover