diff --git a/consensus/consensus_service.go b/consensus/consensus_service.go
index 92926e1a6..51dc251c8 100644
--- a/consensus/consensus_service.go
+++ b/consensus/consensus_service.go
@@ -551,7 +551,9 @@ func (consensus *Consensus) checkConsensusMessage(message *msg_pb.Message, publi
 	// just ignore consensus check for the first time when node join
 	if consensus.ignoreViewIDCheck {
 		consensus.viewID = viewID
-		consensus.ToggleConsensusCheck()
+		consensus.mutex.Lock()
+		consensus.ignoreViewIDCheck = false
+		consensus.mutex.Unlock()
 		return nil
 	} else if viewID != consensus.viewID {
 		utils.GetLogInstance().Warn("Wrong consensus Id", "myViewId", consensus.viewID, "theirViewId", viewID, "consensus", consensus)
@@ -566,6 +568,31 @@ func (consensus *Consensus) checkConsensusMessage(message *msg_pb.Message, publi
 	return nil
 }
 
+// Check viewID
+func (consensus *Consensus) checkViewID(message *msg_pb.Message) error {
+	consensusMsg := message.GetConsensus()
+	viewID := consensusMsg.ViewId
+
+	// just ignore consensus check for the first time when node join
+	if consensus.ignoreViewIDCheck {
+		consensus.viewID = viewID
+		consensus.mutex.Lock()
+		consensus.ignoreViewIDCheck = false
+		consensus.mutex.Unlock()
+		return nil
+	} else if viewID != consensus.viewID {
+		utils.GetLogger().Warn("wrong consensus id", "myViewId", consensus.viewID, "theirViewId", viewID, "consensus", consensus)
+		// notify state syncing to start
+		select {
+		case consensus.ViewIDLowChan <- struct{}{}:
+		default:
+		}
+
+		return consensus_engine.ErrViewIDNotMatch
+	}
+	return nil
+}
+
 // SetBlockNum sets the blockNum in consensus object, called at node bootstrap
 func (consensus *Consensus) SetBlockNum(blockNum uint64) {
 	consensus.mutex.Lock()
diff --git a/consensus/consensus_v2.go b/consensus/consensus_v2.go
index b5a0d86d8..a21573670 100644
--- a/consensus/consensus_v2.go
+++ b/consensus/consensus_v2.go
@@ -151,7 +151,7 @@ func (consensus *Consensus) onAnnounce(msg *msg_pb.Message) {
 		ctxerror.Log15(utils.GetLogInstance().Warn, err)
 		return
 	}
-
+	//blockObj.Logger(utils.GetLogger()).Debug("received announce", "viewID", recvMsg.ViewID, "msgBlockNum", recvMsg.BlockNum)
 	logMsgs := consensus.pbftLog.GetMessagesByTypeSeqView(msg_pb.MessageType_ANNOUNCE, recvMsg.BlockNum, recvMsg.ViewID)
 	if len(logMsgs) > 0 {
 		if logMsgs[0].BlockHash != blockObj.Header().Hash() {
@@ -160,13 +160,17 @@ func (consensus *Consensus) onAnnounce(msg *msg_pb.Message) {
 		}
 		return
 	}
-
 	blockPayload := make([]byte, len(block))
 	copy(blockPayload[:], block[:])
 	consensus.block = blockPayload
 	consensus.blockHash = recvMsg.BlockHash
 	consensus.pbftLog.AddMessage(recvMsg)
 	consensus.pbftLog.AddBlock(&blockObj)
+
+	if consensus.checkViewID(msg) != nil {
+		utils.GetLogger().Debug("viewID check failed", "viewID", recvMsg.ViewID, "myViewID", consensus.viewID)
+		return
+	}
 	consensus.tryPrepare(blockObj.Header().Hash())
 
 	consensus.consensusTimeout["bootstrap"].Stop()
@@ -315,6 +319,9 @@ func (consensus *Consensus) onPrepared(msg *msg_pb.Message) {
 		return
 	}
 	if recvMsg.BlockNum < consensus.blockNum {
+		utils.GetLogger().Debug("old block received, ignoring",
+			"receivedNumber", recvMsg.BlockNum,
+			"expectedNumber", consensus.blockNum)
 		return
 	}
 
@@ -359,10 +366,24 @@ func (consensus *Consensus) onPrepared(msg *msg_pb.Message) {
 		return
 	}
 
+	// TODO ek/cm - make sure we update blocks for syncing
 	consensus.pbftLog.AddMessage(recvMsg)
-	if recvMsg.BlockNum > consensus.blockNum || consensus.phase != Prepare || recvMsg.ViewID != consensus.viewID {
+	if consensus.checkViewID(msg) != nil {
+		utils.GetLogger().Debug("viewID check failed", "viewID", recvMsg.ViewID, "myViewID", consensus.viewID)
+		return
+	}
+	if recvMsg.BlockNum > consensus.blockNum {
+		utils.GetLogger().Debug("future block received, ignoring",
+			"receivedNumber", recvMsg.BlockNum,
+			"expectedNumber", consensus.blockNum)
 		return
 	}
+	if consensus.phase != Prepare {
+		utils.GetLogger().Debug("we are in a wrong phase",
+			"actualPhase", consensus.phase,
+			"expectedPhase", Prepare)
+		// return    // TODO: check if we should return
+	}
 
 	consensus.aggregatedPrepareSig = &deserializedMultiSig
 	consensus.prepareBitmap = mask
@@ -575,6 +596,11 @@ func (consensus *Consensus) onCommitted(msg *msg_pb.Message) {
 
 	consensus.pbftLog.AddMessage(recvMsg)
 
+	if consensus.checkViewID(msg) != nil {
+		utils.GetLogger().Debug("viewID check failed", "viewID", recvMsg.ViewID, "myViewID", consensus.viewID)
+		return
+	}
+
 	if recvMsg.BlockNum > consensus.blockNum || consensus.phase != Commit || recvMsg.ViewID != consensus.viewID {
 		return
 	}
@@ -688,6 +714,9 @@ func (consensus *Consensus) Start(blockChannel chan *types.Block, stopChan chan
 			case <-ticker.C:
 				if !consensus.PubKey.IsEqual(consensus.LeaderPubKey) {
 					for k, v := range consensus.consensusTimeout {
+						if consensus.mode.Mode() == Syncing {
+							v.Stop()
+						}
 						if !v.CheckExpire() {
 							continue
 						}
diff --git a/consensus/view_change.go b/consensus/view_change.go
index ad384c08a..50bbe2968 100644
--- a/consensus/view_change.go
+++ b/consensus/view_change.go
@@ -31,6 +31,7 @@ type Mode int
 const (
 	Normal Mode = iota
 	ViewChanging
+	Syncing
 )
 
 // PbftMode contains mode and viewID of viewchanging
@@ -52,6 +53,11 @@ func (pm *PbftMode) SetMode(m Mode) {
 	pm.mode = m
 }
 
+// SetMode set mode for consensus
+func (consensus *Consensus) SetMode(m Mode) {
+	consensus.mode.mode = m
+}
+
 // ViewID return the current viewchanging id
 func (pm *PbftMode) ViewID() uint32 {
 	return pm.viewID
@@ -108,7 +114,7 @@ func (consensus *Consensus) getIndexOfPubKey(pubKey *bls.PublicKey) int {
 
 // ResetViewChangeState reset the state for viewchange
 func (consensus *Consensus) ResetViewChangeState() {
-	consensus.mode.SetMode(Normal)
+	consensus.SetMode(Normal)
 	bhpBitmap, _ := bls_cosi.NewMask(consensus.PublicKeys, nil)
 	nilBitmap, _ := bls_cosi.NewMask(consensus.PublicKeys, nil)
 	consensus.bhpBitmap = bhpBitmap
@@ -138,8 +144,8 @@ func (consensus *Consensus) startViewChange(viewID uint32) {
 			consensus.consensusTimeout[k].Stop()
 		}
 	}
-	consensus.mode.SetMode(ViewChanging)
-	consensus.mode.SetViewID(viewID)
+	consensus.SetMode(ViewChanging)
+	consensus.SetViewID(viewID)
 	nextLeaderKey := consensus.GetNextLeaderKey()
 	consensus.LeaderPubKey = consensus.GetNextLeaderKey()
 	if nextLeaderKey.IsEqual(consensus.PubKey) {
@@ -161,7 +167,7 @@ func (consensus *Consensus) startViewChange(viewID uint32) {
 // new leader send new view message
 func (consensus *Consensus) startNewView() {
 	utils.GetLogInstance().Info("startNewView", "viewID", consensus.mode.GetViewID())
-	consensus.mode.SetMode(Normal)
+	consensus.SetMode(Normal)
 	consensus.switchPhase(Announce)
 
 	msgToSend := consensus.constructNewViewMessage()
@@ -201,7 +207,7 @@ func (consensus *Consensus) onViewChange(msg *msg_pb.Message) {
 	consensus.vcLock.Lock()
 	defer consensus.vcLock.Unlock()
 
-	consensus.mode.SetMode(ViewChanging)
+	consensus.SetMode(ViewChanging)
 	consensus.mode.SetViewID(recvMsg.ViewID)
 
 	_, ok1 := consensus.nilSigs[consensus.SelfAddress]
@@ -289,7 +295,7 @@ func (consensus *Consensus) onViewChange(msg *msg_pb.Message) {
 	}
 
 	if (len(consensus.bhpSigs) + len(consensus.nilSigs)) >= ((len(consensus.PublicKeys)*2)/3 + 1) {
-		consensus.mode.SetMode(Normal)
+		consensus.SetMode(Normal)
 		consensus.LeaderPubKey = consensus.PubKey
 		if len(consensus.m1Payload) == 0 {
 			consensus.phase = Announce
diff --git a/node/node_syncing.go b/node/node_syncing.go
index 525c35b75..4cf3ca02d 100644
--- a/node/node_syncing.go
+++ b/node/node_syncing.go
@@ -12,6 +12,7 @@ import (
 	"github.com/harmony-one/harmony/api/service/syncing"
 	"github.com/harmony-one/harmony/api/service/syncing/downloader"
 	downloader_pb "github.com/harmony-one/harmony/api/service/syncing/downloader/proto"
+	"github.com/harmony-one/harmony/consensus"
 	"github.com/harmony-one/harmony/core"
 	"github.com/harmony-one/harmony/core/types"
 	nodeconfig "github.com/harmony-one/harmony/internal/configs/node"
@@ -104,6 +105,7 @@ SyncingLoop:
 				utils.GetLogInstance().Debug("[SYNC] out of sync, doing syncing", "willJoinConsensus", willJoinConsensus)
 				node.stateMutex.Lock()
 				node.State = NodeNotInSync
+				node.Consensus.SetMode(consensus.Syncing)
 				node.stateMutex.Unlock()
 				node.stateSync.SyncLoop(bc, worker, willJoinConsensus, false)
 				getLogger().Debug("now in sync")
@@ -112,6 +114,8 @@ SyncingLoop:
 					node.stateMutex.Lock()
 					node.State = NodeReadyForConsensus
 					node.stateMutex.Unlock()
+					node.Consensus.SetMode(consensus.Normal)
+					node.Consensus.SetBlockNum(node.Consensus.ChainReader.CurrentHeader().Number.Uint64() + 1)
 					node.Consensus.ToggleConsensusCheck()
 				}
 			}