standby server: save Running info correctly

Running should be true when Start, and set to false when switching to
the other mode.

server/standby_server.go

@@ -30,6 +30,7 @@ type StandbyServerConfig struct {
 }
 
 type standbyInfo struct {
+	// stay running in standby mode
 	Running      bool
 	Cluster      []*machineMessage
 	SyncInterval float64
@@ -78,12 +79,16 @@ func (s *StandbyServer) Start() {
 	s.removeNotify = make(chan bool)
 	s.closeChan = make(chan bool)
 
+	s.Running = true
+	if err := s.saveInfo(); err != nil {
+		log.Warnf("error saving cluster info for standby")
+	}
+
 	s.routineGroup.Add(1)
 	go func() {
 		defer s.routineGroup.Done()
 		s.monitorCluster()
 	}()
-	s.Running = true
 }
 
 // Stop stops the server gracefully.
@@ -97,11 +102,6 @@ func (s *StandbyServer) Stop() {
 
 	close(s.closeChan)
 	s.routineGroup.Wait()
-
-	if err := s.saveInfo(); err != nil {
-		log.Warnf("error saving cluster info for standby")
-	}
-	s.Running = false
 }
 
 // RemoveNotify notifies the server is removed from standby mode and ready
@@ -204,6 +204,10 @@ func (s *StandbyServer) monitorCluster() {
 		}
 
 		log.Infof("join through leader %v", leader.PeerURL)
+		s.Running = false
+		if err := s.saveInfo(); err != nil {
+			log.Warnf("error saving cluster info for standby")
+		}
 		go func() {
 			s.Stop()
 			close(s.removeNotify)