diff --git a/.mergify.yml b/.mergify.yml
new file mode 100644
index 0000000000..865a31d66a
--- /dev/null
+++ b/.mergify.yml
@@ -0,0 +1,59 @@
+pull_request_rules:
+  - name: Squash merge rule to dev
+    conditions:
+      # applied for merge to the dev branch
+      - base=dev
+      # no unresolved threads
+      - "#review-threads-unresolved=0"
+      # Approved by two reviewers
+      - "#approved-reviews-by>=2"
+      # no unverified commit
+      - "#commits-unverified=0"
+      # Travis ci succeeded
+      - "check-success=Travis CI - Pull Request"
+      # git guardian succeeded
+      - "check-success=GitGuardian Security Checks"
+      # PR is not a draft
+      - -draft
+      # PR is not conflicting with the base branch
+      - -conflict
+      # conditions to avoid auto merge mistakes
+      # PR title doesn't have wip (not case sensitive)
+      - -title~=(?i)wip
+      # PR doesn't have WIP label (not case sensitive)
+      - label!=(?i)wip
+      # ready-to-merge is required to trigger the merge
+      - label=ready-to-merge
+    actions:
+      merge:
+        method: squash
+  - name: merge rule to main
+    conditions:
+      # from the dev branch : no direct PR to main
+      - head=dev
+      # applied for merge to the dev branch
+      - base=main
+      # no unresolved threads
+      - "#review-threads-unresolved=0"
+      # Approved by two reviewers
+      - "#approved-reviews-by>=2"
+      # no unverified commit
+      - "#commits-unverified=0"
+      # Travis ci succeeded
+      - "check-success=Travis CI - Pull Request"
+      # git guardian succeeded
+      - "check-success=GitGuardian Security Checks"
+      # PR is not a draft
+      - -draft
+      # PR is not conflicting with the base branch
+      - -conflict
+      # conditions to avoid auto merge mistakes
+      # PR title doesn't have wip (not case sensitive)
+      - -title~=(?i)wip
+      # PR doesn't have WIP label (not case sensitive)
+      - label!=(?i)wip
+      # ready-to-merge is required to trigger the merge
+      - label=ready-to-merge
+    actions:
+      merge:
+        method: merge
\ No newline at end of file
diff --git a/api/service/legacysync/syncing_test.go b/api/service/legacysync/syncing_test.go
index bc17aeaec6..7d99051c76 100644
--- a/api/service/legacysync/syncing_test.go
+++ b/api/service/legacysync/syncing_test.go
@@ -12,7 +12,7 @@ import (
 	"time"
 
 	nodeconfig "github.com/harmony-one/harmony/internal/configs/node"
-	peer "github.com/libp2p/go-libp2p-core/peer"
+	peer "github.com/libp2p/go-libp2p/core/peer"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/harmony-one/harmony/api/service/legacysync/downloader"
diff --git a/api/service/stagedstreamsync/const.go b/api/service/stagedstreamsync/const.go
index 0e6bc6e2cf..5c735d764b 100644
--- a/api/service/stagedstreamsync/const.go
+++ b/api/service/stagedstreamsync/const.go
@@ -14,7 +14,10 @@ const (
 	BlockByHashesUpperCap int = 10 // number of get blocks by hashes upper cap
 	BlockByHashesLowerCap int = 3  // number of get blocks by hashes lower cap
 
-	LastMileBlocksThreshold int = 10
+	LastMileBlocksThreshold int    = 10
+	SyncLoopBatchSize       uint32 = 30  // maximum size for one query of block hashes
+	VerifyHeaderBatchSize   uint64 = 100 // block chain header verification batch size (not used for now)
+	LastMileBlocksSize             = 50
 
 	// SoftQueueCap is the soft cap of size in resultQueue. When the queue size is larger than this limit,
 	// no more request will be assigned to workers to wait for InsertChain to finish.
@@ -50,8 +53,15 @@ type (
 		// config for beacon config
 		BHConfig *BeaconHelperConfig
 
+		// use memory db
+		UseMemDB bool
+
 		// log the stage progress
 		LogProgress bool
+
+		// logs every single process and error to help debugging stream sync
+		// DebugMode is not accessible to the end user and is only an aid for development
+		DebugMode bool
 	}
 
 	// BeaconHelperConfig is the extra config used for beaconHelper which uses
diff --git a/api/service/stagedstreamsync/default_stages.go b/api/service/stagedstreamsync/default_stages.go
index 6e4808738f..55986ff6e8 100644
--- a/api/service/stagedstreamsync/default_stages.go
+++ b/api/service/stagedstreamsync/default_stages.go
@@ -15,11 +15,13 @@ var DefaultForwardOrder = ForwardOrder{
 	BlockBodies,
 	// Stages below don't use Internet
 	States,
+	LastMile,
 	Finish,
 }
 
 var DefaultRevertOrder = RevertOrder{
 	Finish,
+	LastMile,
 	States,
 	BlockBodies,
 	ShortRange,
@@ -29,6 +31,7 @@ var DefaultRevertOrder = RevertOrder{
 
 var DefaultCleanUpOrder = CleanUpOrder{
 	Finish,
+	LastMile,
 	States,
 	BlockBodies,
 	ShortRange,
@@ -42,6 +45,7 @@ func DefaultStages(ctx context.Context,
 	srCfg StageShortRangeCfg,
 	bodiesCfg StageBodiesCfg,
 	statesCfg StageStatesCfg,
+	lastMileCfg StageLastMileCfg,
 	finishCfg StageFinishCfg,
 ) []*Stage {
 
@@ -50,6 +54,7 @@ func DefaultStages(ctx context.Context,
 	handlerStageEpochSync := NewStageEpoch(seCfg)
 	handlerStageBodies := NewStageBodies(bodiesCfg)
 	handlerStageStates := NewStageStates(statesCfg)
+	handlerStageLastMile := NewStageLastMile(lastMileCfg)
 	handlerStageFinish := NewStageFinish(finishCfg)
 
 	return []*Stage{
@@ -78,6 +83,11 @@ func DefaultStages(ctx context.Context,
 			Description: "Update Blockchain State",
 			Handler:     handlerStageStates,
 		},
+		{
+			ID:          LastMile,
+			Description: "update status for blocks after sync and update last mile blocks as well",
+			Handler:     handlerStageLastMile,
+		},
 		{
 			ID:          Finish,
 			Description: "Finalize Changes",
diff --git a/api/service/stagedstreamsync/downloader.go b/api/service/stagedstreamsync/downloader.go
index 668698f107..96add97fd3 100644
--- a/api/service/stagedstreamsync/downloader.go
+++ b/api/service/stagedstreamsync/downloader.go
@@ -8,6 +8,7 @@ import (
 	"github.com/ethereum/go-ethereum/event"
 	"github.com/rs/zerolog"
 
+	"github.com/harmony-one/harmony/consensus"
 	"github.com/harmony-one/harmony/core"
 	nodeconfig "github.com/harmony-one/harmony/internal/configs/node"
 	"github.com/harmony-one/harmony/internal/utils"
@@ -37,7 +38,7 @@ type (
 )
 
 // NewDownloader creates a new downloader
-func NewDownloader(host p2p.Host, bc core.BlockChain, dbDir string, isBeaconNode bool, config Config) *Downloader {
+func NewDownloader(host p2p.Host, bc core.BlockChain, consensus *consensus.Consensus, dbDir string, isBeaconNode bool, config Config) *Downloader {
 	config.fixValues()
 
 	sp := sync.NewProtocol(sync.Config{
@@ -67,8 +68,8 @@ func NewDownloader(host p2p.Host, bc core.BlockChain, dbDir string, isBeaconNode
 
 	ctx, cancel := context.WithCancel(context.Background())
 
-	//TODO: use mem db should be in config file
-	stagedSyncInstance, err := CreateStagedSync(ctx, bc, dbDir, false, isBeaconNode, sp, config, logger, config.LogProgress)
+	// create an instance of staged sync for the downloader
+	stagedSyncInstance, err := CreateStagedSync(ctx, bc, consensus, dbDir, isBeaconNode, sp, config, logger)
 	if err != nil {
 		cancel()
 		return nil
@@ -189,6 +190,7 @@ func (d *Downloader) waitForBootFinish() {
 func (d *Downloader) loop() {
 	ticker := time.NewTicker(10 * time.Second)
 	defer ticker.Stop()
+
 	// for shard chain and beacon chain node, first we start with initSync=true to
 	// make sure it goes through the long range sync first.
 	// for epoch chain we do only need to go through epoch sync process
@@ -208,7 +210,8 @@ func (d *Downloader) loop() {
 			go trigger()
 
 		case <-d.downloadC:
-			addedBN, err := d.stagedSyncInstance.doSync(d.ctx, initSync)
+			bnBeforeSync := d.bc.CurrentBlock().NumberU64()
+			estimatedHeight, addedBN, err := d.stagedSyncInstance.doSync(d.ctx, initSync)
 			if err != nil {
 				//TODO: if there is a bad block which can't be resolved
 				if d.stagedSyncInstance.invalidBlock.Active {
@@ -216,13 +219,14 @@ func (d *Downloader) loop() {
 					// if many streams couldn't solve it, then that's an unresolvable bad block
 					if numTriedStreams >= d.config.InitStreams {
 						if !d.stagedSyncInstance.invalidBlock.IsLogged {
-							fmt.Println("unresolvable bad block:", d.stagedSyncInstance.invalidBlock.Number)
+							d.logger.Error().
+								Uint64("bad block number", d.stagedSyncInstance.invalidBlock.Number).
+								Msg(WrapStagedSyncMsg("unresolvable bad block"))
 							d.stagedSyncInstance.invalidBlock.IsLogged = true
 						}
 						//TODO: if we don't have any new or untried stream in the list, sleep or panic
 					}
 				}
-
 				// If any error happens, sleep 5 seconds and retry
 				d.logger.Error().
 					Err(err).
@@ -242,16 +246,27 @@ func (d *Downloader) loop() {
 					Uint32("shard", d.bc.ShardID()).
 					Msg(WrapStagedSyncMsg("sync finished"))
 			}
-
+			// If block number has been changed, trigger another sync
 			if addedBN != 0 {
-				// If block number has been changed, trigger another sync
 				go trigger()
+				// try to add last mile from pub-sub (blocking)
+				if d.bh != nil {
+					d.bh.insertSync()
+				}
 			}
-			// try to add last mile from pub-sub (blocking)
-			if d.bh != nil {
-				d.bh.insertSync()
+			// if last doSync needed only to add a few blocks less than LastMileBlocksThreshold and
+			// the node is fully synced now, then switch to short range
+			// the reason why we need to check distanceBeforeSync is because, if it was long distance,
+			// very likely, there are a couple of new blocks have been added to the other nodes which
+			// we should still stay in long range and check them.
+			bnAfterSync := d.bc.CurrentBlock().NumberU64()
+			distanceBeforeSync := estimatedHeight - bnBeforeSync
+			distanceAfterSync := estimatedHeight - bnAfterSync
+			if estimatedHeight > 0 && addedBN > 0 &&
+				distanceBeforeSync <= uint64(LastMileBlocksThreshold) &&
+				distanceAfterSync <= uint64(LastMileBlocksThreshold) {
+				initSync = false
 			}
-			initSync = false
 
 		case <-d.closeC:
 			return
diff --git a/api/service/stagedstreamsync/downloaders.go b/api/service/stagedstreamsync/downloaders.go
index 2df8b74aab..583f3e1523 100644
--- a/api/service/stagedstreamsync/downloaders.go
+++ b/api/service/stagedstreamsync/downloaders.go
@@ -2,6 +2,7 @@ package stagedstreamsync
 
 import (
 	"github.com/harmony-one/abool"
+	"github.com/harmony-one/harmony/consensus"
 	"github.com/harmony-one/harmony/core"
 	"github.com/harmony-one/harmony/p2p"
 )
@@ -15,7 +16,7 @@ type Downloaders struct {
 }
 
 // NewDownloaders creates Downloaders for sync of multiple blockchains
-func NewDownloaders(host p2p.Host, bcs []core.BlockChain, dbDir string, config Config) *Downloaders {
+func NewDownloaders(host p2p.Host, bcs []core.BlockChain, consensus *consensus.Consensus, dbDir string, config Config) *Downloaders {
 	ds := make(map[uint32]*Downloader)
 	isBeaconNode := len(bcs) == 1
 	for _, bc := range bcs {
@@ -25,7 +26,7 @@ func NewDownloaders(host p2p.Host, bcs []core.BlockChain, dbDir string, config C
 		if _, ok := ds[bc.ShardID()]; ok {
 			continue
 		}
-		ds[bc.ShardID()] = NewDownloader(host, bc, dbDir, isBeaconNode, config)
+		ds[bc.ShardID()] = NewDownloader(host, bc, consensus, dbDir, isBeaconNode, config)
 	}
 	return &Downloaders{
 		ds:     ds,
diff --git a/api/service/stagedstreamsync/service.go b/api/service/stagedstreamsync/service.go
index 40fbf7097c..f7ffd7f2d9 100644
--- a/api/service/stagedstreamsync/service.go
+++ b/api/service/stagedstreamsync/service.go
@@ -1,6 +1,7 @@
 package stagedstreamsync
 
 import (
+	"github.com/harmony-one/harmony/consensus"
 	"github.com/harmony-one/harmony/core"
 	"github.com/harmony-one/harmony/p2p"
 )
@@ -11,9 +12,9 @@ type StagedStreamSyncService struct {
 }
 
 // NewService creates a new downloader service
-func NewService(host p2p.Host, bcs []core.BlockChain, config Config, dbDir string) *StagedStreamSyncService {
+func NewService(host p2p.Host, bcs []core.BlockChain, consensus *consensus.Consensus, config Config, dbDir string) *StagedStreamSyncService {
 	return &StagedStreamSyncService{
-		Downloaders: NewDownloaders(host, bcs, dbDir, config),
+		Downloaders: NewDownloaders(host, bcs, consensus, dbDir, config),
 	}
 }
 
diff --git a/api/service/stagedstreamsync/short_range_helper.go b/api/service/stagedstreamsync/short_range_helper.go
index e43b3c6916..42327c78df 100644
--- a/api/service/stagedstreamsync/short_range_helper.go
+++ b/api/service/stagedstreamsync/short_range_helper.go
@@ -207,6 +207,12 @@ func (sh *srHelper) removeStreams(sts []sttypes.StreamID) {
 	}
 }
 
+func (sh *srHelper) streamsFailed(sts []sttypes.StreamID, reason string) {
+	for _, st := range sts {
+		sh.syncProtocol.StreamFailed(st, reason)
+	}
+}
+
 // blameAllStreams only not to blame all whitelisted streams when the it's not the last block signature verification failed.
 func (sh *srHelper) blameAllStreams(blocks types.Blocks, errIndex int, err error) bool {
 	if errors.As(err, &emptySigVerifyErr) && errIndex == len(blocks)-1 {
diff --git a/api/service/stagedstreamsync/stage_bodies.go b/api/service/stagedstreamsync/stage_bodies.go
index 62309b76df..4996ea78b7 100644
--- a/api/service/stagedstreamsync/stage_bodies.go
+++ b/api/service/stagedstreamsync/stage_bodies.go
@@ -10,6 +10,7 @@ import (
 	"github.com/harmony-one/harmony/core/types"
 	"github.com/harmony-one/harmony/internal/utils"
 	sttypes "github.com/harmony-one/harmony/p2p/stream/types"
+	"github.com/harmony-one/harmony/shard"
 	"github.com/ledgerwatch/erigon-lib/kv"
 	"github.com/pkg/errors"
 )
@@ -60,6 +61,11 @@ func (b *StageBodies) Exec(ctx context.Context, firstCycle bool, invalidBlockRev
 		return nil
 	}
 
+	// shouldn't execute for epoch chain
+	if b.configs.bc.ShardID() == shard.BeaconChainShardID && !s.state.isBeaconNode {
+		return nil
+	}
+
 	maxHeight := s.state.status.targetBN
 	currentHead := b.configs.bc.CurrentBlock().NumberU64()
 	if currentHead >= maxHeight {
@@ -77,7 +83,7 @@ func (b *StageBodies) Exec(ctx context.Context, firstCycle bool, invalidBlockRev
 		return errV
 	}
 
-	if currProgress == 0 {
+	if currProgress <= currentHead {
 		if err := b.cleanAllBlockDBs(ctx); err != nil {
 			return err
 		}
@@ -209,7 +215,7 @@ func (b *StageBodies) redownloadBadBlock(ctx context.Context, s *StageState) err
 		isOneOfTheBadStreams := false
 		for _, id := range s.state.invalidBlock.StreamID {
 			if id == stid {
-				b.configs.protocol.RemoveStream(stid)
+				b.configs.protocol.StreamFailed(stid, "re-download bad block from this stream failed")
 				isOneOfTheBadStreams = true
 				break
 			}
diff --git a/api/service/stagedstreamsync/stage_epoch.go b/api/service/stagedstreamsync/stage_epoch.go
index 394a1d5d69..2c51aa1f94 100644
--- a/api/service/stagedstreamsync/stage_epoch.go
+++ b/api/service/stagedstreamsync/stage_epoch.go
@@ -5,6 +5,7 @@ import (
 
 	"github.com/harmony-one/harmony/core"
 	"github.com/harmony-one/harmony/internal/utils"
+	sttypes "github.com/harmony-one/harmony/p2p/stream/types"
 	"github.com/harmony-one/harmony/shard"
 	"github.com/ledgerwatch/erigon-lib/kv"
 	"github.com/pkg/errors"
@@ -51,9 +52,12 @@ func (sr *StageEpoch) Exec(ctx context.Context, firstCycle bool, invalidBlockRev
 	n, err := sr.doShortRangeSyncForEpochSync(ctx, s)
 	s.state.inserted = n
 	if err != nil {
+		utils.Logger().Info().Err(err).Msg("short range for epoch sync failed")
 		return err
 	}
-
+	if n > 0 {
+		utils.Logger().Info().Err(err).Int("blocks inserted", n).Msg("epoch sync short range blocks inserted successfully")
+	}
 	useInternalTx := tx == nil
 	if useInternalTx {
 		var err error
@@ -108,30 +112,13 @@ func (sr *StageEpoch) doShortRangeSyncForEpochSync(ctx context.Context, s *Stage
 		return 0, nil
 	}
 
-	////////////////////////////////////////////////////////
-	hashChain, whitelist, err := sh.getHashChain(ctx, bns)
+	blocks, streamID, err := sh.getBlocksChain(ctx, bns)
 	if err != nil {
+		if errors.Is(err, context.DeadlineExceeded) || errors.Is(err, context.Canceled) {
+			return 0, nil
+		}
 		return 0, errors.Wrap(err, "getHashChain")
 	}
-	if len(hashChain) == 0 {
-		// short circuit for no sync is needed
-		return 0, nil
-	}
-	blocks, streamID, err := sh.getBlocksByHashes(ctx, hashChain, whitelist)
-	if err != nil {
-		utils.Logger().Warn().Err(err).Msg("epoch sync getBlocksByHashes failed")
-		if !errors.Is(err, context.Canceled) {
-			sh.removeStreams(whitelist) // Remote nodes cannot provide blocks with target hashes
-		}
-		return 0, errors.Wrap(err, "epoch sync getBlocksByHashes")
-	}
-	///////////////////////////////////////////////////////
-	// TODO: check this
-	// blocks, streamID, err := sh.getBlocksChain(bns)
-	// if err != nil {
-	// 	return 0, errors.Wrap(err, "getHashChain")
-	// }
-	///////////////////////////////////////////////////////
 	if len(blocks) == 0 {
 		// short circuit for no sync is needed
 		return 0, nil
@@ -141,12 +128,9 @@ func (sr *StageEpoch) doShortRangeSyncForEpochSync(ctx context.Context, s *Stage
 	numBlocksInsertedShortRangeHistogramVec.With(s.state.promLabels()).Observe(float64(n))
 	if err != nil {
 		utils.Logger().Info().Err(err).Int("blocks inserted", n).Msg("Insert block failed")
-		sh.removeStreams(streamID) // Data provided by remote nodes is corrupted
+		sh.streamsFailed([]sttypes.StreamID{streamID}, "corrupted data")
 		return n, err
 	}
-	if n > 0 {
-		utils.Logger().Info().Int("blocks inserted", n).Msg("Insert block success")
-	}
 	return n, nil
 }
 
diff --git a/api/service/stagedstreamsync/stage_lastmile.go b/api/service/stagedstreamsync/stage_lastmile.go
new file mode 100644
index 0000000000..157dcc3680
--- /dev/null
+++ b/api/service/stagedstreamsync/stage_lastmile.go
@@ -0,0 +1,109 @@
+package stagedstreamsync
+
+import (
+	"context"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/harmony-one/harmony/core"
+	"github.com/harmony-one/harmony/shard"
+	"github.com/ledgerwatch/erigon-lib/kv"
+)
+
+type StageLastMile struct {
+	configs StageLastMileCfg
+}
+
+type StageLastMileCfg struct {
+	ctx context.Context
+	bc  core.BlockChain
+	db  kv.RwDB
+}
+
+func NewStageLastMile(cfg StageLastMileCfg) *StageLastMile {
+	return &StageLastMile{
+		configs: cfg,
+	}
+}
+
+func NewStageLastMileCfg(ctx context.Context, bc core.BlockChain, db kv.RwDB) StageLastMileCfg {
+	return StageLastMileCfg{
+		ctx: ctx,
+		bc:  bc,
+		db:  db,
+	}
+}
+
+func (lm *StageLastMile) Exec(ctx context.Context, firstCycle bool, invalidBlockRevert bool, s *StageState, reverter Reverter, tx kv.RwTx) (err error) {
+
+	// no need to download the last mile blocks if we are redoing the stages because of bad block
+	if invalidBlockRevert {
+		return nil
+	}
+
+	// shouldn't execute for epoch chain
+	if lm.configs.bc.ShardID() == shard.BeaconChainShardID && !s.state.isBeaconNode {
+		return nil
+	}
+
+	bc := lm.configs.bc
+
+	// update last mile blocks if any
+	parentHash := bc.CurrentBlock().Hash()
+	var hashes []common.Hash
+	for {
+		block := s.state.getBlockFromLastMileBlocksByParentHash(parentHash)
+		if block == nil {
+			break
+		}
+		err = s.state.UpdateBlockAndStatus(block, bc, false)
+		if err != nil {
+			s.state.RollbackLastMileBlocks(ctx, hashes)
+			return err
+		}
+		hashes = append(hashes, block.Hash())
+		parentHash = block.Hash()
+	}
+	s.state.purgeLastMileBlocksFromCache()
+
+	return nil
+}
+
+func (lm *StageLastMile) Revert(ctx context.Context, firstCycle bool, u *RevertState, s *StageState, tx kv.RwTx) (err error) {
+	useInternalTx := tx == nil
+	if useInternalTx {
+		tx, err = lm.configs.db.BeginRw(lm.configs.ctx)
+		if err != nil {
+			return err
+		}
+		defer tx.Rollback()
+	}
+
+	if err = u.Done(tx); err != nil {
+		return err
+	}
+
+	if useInternalTx {
+		if err = tx.Commit(); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (lm *StageLastMile) CleanUp(ctx context.Context, firstCycle bool, p *CleanUpState, tx kv.RwTx) (err error) {
+	useInternalTx := tx == nil
+	if useInternalTx {
+		tx, err = lm.configs.db.BeginRw(lm.configs.ctx)
+		if err != nil {
+			return err
+		}
+		defer tx.Rollback()
+	}
+
+	if useInternalTx {
+		if err = tx.Commit(); err != nil {
+			return err
+		}
+	}
+	return nil
+}
diff --git a/api/service/stagedstreamsync/stage_short_range.go b/api/service/stagedstreamsync/stage_short_range.go
index 8fb2f3059e..54534bfbb1 100644
--- a/api/service/stagedstreamsync/stage_short_range.go
+++ b/api/service/stagedstreamsync/stage_short_range.go
@@ -44,6 +44,7 @@ func (sr *StageShortRange) Exec(ctx context.Context, firstCycle bool, invalidBlo
 		return nil
 	}
 
+	// shouldn't execute for epoch chain
 	if sr.configs.bc.ShardID() == shard.BeaconChainShardID && !s.state.isBeaconNode {
 		return nil
 	}
@@ -52,8 +53,12 @@ func (sr *StageShortRange) Exec(ctx context.Context, firstCycle bool, invalidBlo
 	n, err := sr.doShortRangeSync(ctx, s)
 	s.state.inserted = n
 	if err != nil {
+		utils.Logger().Info().Err(err).Msg("short range sync failed")
 		return err
 	}
+	if n > 0 {
+		utils.Logger().Info().Err(err).Int("blocks inserted", n).Msg("short range blocks inserted successfully")
+	}
 
 	useInternalTx := tx == nil
 	if useInternalTx {
@@ -98,6 +103,9 @@ func (sr *StageShortRange) doShortRangeSync(ctx context.Context, s *StageState)
 	blkNums := sh.prepareBlockHashNumbers(curBN)
 	hashChain, whitelist, err := sh.getHashChain(ctx, blkNums)
 	if err != nil {
+		if errors.Is(err, context.DeadlineExceeded) || errors.Is(err, context.Canceled) {
+			return 0, nil
+		}
 		return 0, errors.Wrap(err, "getHashChain")
 	}
 
@@ -114,37 +122,34 @@ func (sr *StageShortRange) doShortRangeSync(ctx context.Context, s *StageState)
 
 	s.state.status.setTargetBN(expEndBN)
 
-	s.state.status.startSyncing()
-	defer func() {
-		utils.Logger().Info().Msg("short range finished syncing")
-		s.state.status.finishSyncing()
-	}()
-
 	blocks, stids, err := sh.getBlocksByHashes(ctx, hashChain, whitelist)
 	if err != nil {
 		utils.Logger().Warn().Err(err).Msg("getBlocksByHashes failed")
-		if !errors.Is(err, context.Canceled) {
-			sh.removeStreams(whitelist) // Remote nodes cannot provide blocks with target hashes
+		if errors.Is(err, context.DeadlineExceeded) || errors.Is(err, context.Canceled) {
+			return 0, errors.Wrap(err, "getBlocksByHashes")
 		}
-		return 0, errors.Wrap(err, "getBlocksByHashes")
+		sh.streamsFailed(whitelist, "remote nodes cannot provide blocks with target hashes")
 	}
 
-	utils.Logger().Info().Int("num blocks", len(blocks)).Msg("getBlockByHashes result")
-
 	n, err := verifyAndInsertBlocks(sr.configs.bc, blocks)
 	numBlocksInsertedShortRangeHistogramVec.With(s.state.promLabels()).Observe(float64(n))
 	if err != nil {
 		utils.Logger().Warn().Err(err).Int("blocks inserted", n).Msg("Insert block failed")
+		// rollback all added new blocks
+		if rbErr := sr.configs.bc.Rollback(hashChain); rbErr != nil {
+			utils.Logger().Error().Err(rbErr).Msg("short range failed to rollback")
+			return 0, rbErr
+		}
+		// fail streams
 		if sh.blameAllStreams(blocks, n, err) {
-			sh.removeStreams(whitelist) // Data provided by remote nodes is corrupted
+			sh.streamsFailed(whitelist, "data provided by remote nodes is corrupted")
 		} else {
 			// It is the last block gives a wrong commit sig. Blame the provider of the last block.
 			st2Blame := stids[len(stids)-1]
-			sh.removeStreams([]sttypes.StreamID{st2Blame})
+			sh.streamsFailed([]sttypes.StreamID{st2Blame}, "the last block provided by stream gives a wrong commit sig")
 		}
-		return n, err
+		return 0, err
 	}
-	utils.Logger().Info().Err(err).Int("blocks inserted", n).Msg("Insert block success")
 
 	return n, nil
 }
diff --git a/api/service/stagedstreamsync/stage_state.go b/api/service/stagedstreamsync/stage_state.go
index 4b237c2916..b8dfb18288 100644
--- a/api/service/stagedstreamsync/stage_state.go
+++ b/api/service/stagedstreamsync/stage_state.go
@@ -10,6 +10,7 @@ import (
 	"github.com/harmony-one/harmony/core"
 	"github.com/harmony-one/harmony/core/types"
 	"github.com/harmony-one/harmony/internal/utils"
+	"github.com/harmony-one/harmony/shard"
 	"github.com/ledgerwatch/erigon-lib/kv"
 	"github.com/rs/zerolog"
 )
@@ -57,6 +58,11 @@ func (stg *StageStates) Exec(ctx context.Context, firstCycle bool, invalidBlockR
 		return nil
 	}
 
+	// shouldn't execute for epoch chain
+	if stg.configs.bc.ShardID() == shard.BeaconChainShardID && !s.state.isBeaconNode {
+		return nil
+	}
+
 	maxHeight := s.state.status.targetBN
 	currentHead := stg.configs.bc.CurrentBlock().NumberU64()
 	if currentHead >= maxHeight {
@@ -144,8 +150,10 @@ func (stg *StageStates) Exec(ctx context.Context, firstCycle bool, invalidBlockR
 
 		if block.NumberU64() != i {
 			s.state.protocol.StreamFailed(streamID, "invalid block with unmatched number is received from stream")
-			invalidBlockHash := block.Hash()
-			reverter.RevertTo(stg.configs.bc.CurrentBlock().NumberU64(), i, invalidBlockHash, streamID)
+			if !invalidBlockRevert {
+				invalidBlockHash := block.Hash()
+				reverter.RevertTo(stg.configs.bc.CurrentBlock().NumberU64(), i, invalidBlockHash, streamID)
+			}
 			return ErrInvalidBlockNumber
 		}
 
diff --git a/api/service/stagedstreamsync/staged_stream_sync.go b/api/service/stagedstreamsync/staged_stream_sync.go
index 6c1eec4c37..3cd8756604 100644
--- a/api/service/stagedstreamsync/staged_stream_sync.go
+++ b/api/service/stagedstreamsync/staged_stream_sync.go
@@ -8,11 +8,16 @@ import (
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/event"
+	"github.com/harmony-one/harmony/consensus"
+	"github.com/harmony-one/harmony/consensus/engine"
 	"github.com/harmony-one/harmony/core"
+	"github.com/harmony-one/harmony/core/types"
+	"github.com/harmony-one/harmony/internal/chain"
 	"github.com/harmony-one/harmony/internal/utils"
 	syncproto "github.com/harmony-one/harmony/p2p/stream/protocols/sync"
 	sttypes "github.com/harmony-one/harmony/p2p/stream/types"
 	"github.com/ledgerwatch/erigon-lib/kv"
+	"github.com/pkg/errors"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/rs/zerolog"
 )
@@ -54,19 +59,22 @@ func (ib *InvalidBlock) addBadStream(bsID sttypes.StreamID) {
 }
 
 type StagedStreamSync struct {
-	bc           core.BlockChain
-	isBeacon     bool
-	isExplorer   bool
-	db           kv.RwDB
-	protocol     syncProtocol
-	isBeaconNode bool
-	gbm          *blockDownloadManager // initialized when finished get block number
-	inserted     int
-	config       Config
-	logger       zerolog.Logger
-	status       *status //TODO: merge this with currentSyncCycle
-	initSync     bool    // if sets to true, node start long range syncing
-	UseMemDB     bool
+	bc             core.BlockChain
+	consensus      *consensus.Consensus
+	isBeacon       bool
+	isExplorer     bool
+	db             kv.RwDB
+	protocol       syncProtocol
+	isBeaconNode   bool
+	gbm            *blockDownloadManager // initialized when finished get block number
+	lastMileBlocks []*types.Block        // last mile blocks to catch up with the consensus
+	lastMileMux    sync.Mutex
+	inserted       int
+	config         Config
+	logger         zerolog.Logger
+	status         *status //TODO: merge this with currentSyncCycle
+	initSync       bool    // if sets to true, node start long range syncing
+	UseMemDB       bool
 
 	revertPoint     *uint64 // used to run stages
 	prevRevertPoint *uint64 // used to get value from outside of staged sync after cycle (for example to notify RPCDaemon)
@@ -249,12 +257,12 @@ func (s *StagedStreamSync) cleanUp(ctx context.Context, fromStage int, db kv.RwD
 // New creates a new StagedStreamSync instance
 func New(
 	bc core.BlockChain,
+	consensus *consensus.Consensus,
 	db kv.RwDB,
 	stagesList []*Stage,
 	isBeacon bool,
 	protocol syncProtocol,
 	isBeaconNode bool,
-	useMemDB bool,
 	config Config,
 	logger zerolog.Logger,
 ) *StagedStreamSync {
@@ -286,22 +294,24 @@ func New(
 	status := newStatus()
 
 	return &StagedStreamSync{
-		bc:           bc,
-		isBeacon:     isBeacon,
-		db:           db,
-		protocol:     protocol,
-		isBeaconNode: isBeaconNode,
-		gbm:          nil,
-		status:       &status,
-		inserted:     0,
-		config:       config,
-		logger:       logger,
-		stages:       stagesList,
-		currentStage: 0,
-		revertOrder:  revertStages,
-		pruningOrder: pruneStages,
-		logPrefixes:  logPrefixes,
-		UseMemDB:     useMemDB,
+		bc:             bc,
+		consensus:      consensus,
+		isBeacon:       isBeacon,
+		db:             db,
+		protocol:       protocol,
+		isBeaconNode:   isBeaconNode,
+		lastMileBlocks: []*types.Block{},
+		gbm:            nil,
+		status:         &status,
+		inserted:       0,
+		config:         config,
+		logger:         logger,
+		stages:         stagesList,
+		currentStage:   0,
+		revertOrder:    revertStages,
+		pruningOrder:   pruneStages,
+		logPrefixes:    logPrefixes,
+		UseMemDB:       config.UseMemDB,
 	}
 }
 
@@ -583,3 +593,133 @@ func (s *StagedStreamSync) EnableStages(ids ...SyncStageID) {
 		}
 	}
 }
+
+func (ss *StagedStreamSync) purgeLastMileBlocksFromCache() {
+	ss.lastMileMux.Lock()
+	ss.lastMileBlocks = nil
+	ss.lastMileMux.Unlock()
+}
+
+// AddLastMileBlock adds the latest a few block into queue for syncing
+// only keep the latest blocks with size capped by LastMileBlocksSize
+func (ss *StagedStreamSync) AddLastMileBlock(block *types.Block) {
+	ss.lastMileMux.Lock()
+	defer ss.lastMileMux.Unlock()
+	if ss.lastMileBlocks != nil {
+		if len(ss.lastMileBlocks) >= LastMileBlocksSize {
+			ss.lastMileBlocks = ss.lastMileBlocks[1:]
+		}
+		ss.lastMileBlocks = append(ss.lastMileBlocks, block)
+	}
+}
+
+func (ss *StagedStreamSync) getBlockFromLastMileBlocksByParentHash(parentHash common.Hash) *types.Block {
+	ss.lastMileMux.Lock()
+	defer ss.lastMileMux.Unlock()
+	for _, block := range ss.lastMileBlocks {
+		ph := block.ParentHash()
+		if ph == parentHash {
+			return block
+		}
+	}
+	return nil
+}
+
+func (ss *StagedStreamSync) addConsensusLastMile(bc core.BlockChain, cs *consensus.Consensus) ([]common.Hash, error) {
+	curNumber := bc.CurrentBlock().NumberU64()
+	var hashes []common.Hash
+
+	err := cs.GetLastMileBlockIter(curNumber+1, func(blockIter *consensus.LastMileBlockIter) error {
+		for {
+			block := blockIter.Next()
+			if block == nil {
+				break
+			}
+			if _, err := bc.InsertChain(types.Blocks{block}, true); err != nil {
+				return errors.Wrap(err, "failed to InsertChain")
+			}
+			hashes = append(hashes, block.Header().Hash())
+		}
+		return nil
+	})
+	return hashes, err
+}
+
+func (ss *StagedStreamSync) RollbackLastMileBlocks(ctx context.Context, hashes []common.Hash) error {
+	if len(hashes) == 0 {
+		return nil
+	}
+	utils.Logger().Info().
+		Interface("block", ss.bc.CurrentBlock()).
+		Msg("[STAGED_STREAM_SYNC] Rolling back last mile blocks")
+	if err := ss.bc.Rollback(hashes); err != nil {
+		utils.Logger().Error().Err(err).
+			Msg("[STAGED_STREAM_SYNC] failed to rollback last mile blocks")
+		return err
+	}
+	return nil
+}
+
+// UpdateBlockAndStatus updates block and its status in db
+func (ss *StagedStreamSync) UpdateBlockAndStatus(block *types.Block, bc core.BlockChain, verifyAllSig bool) error {
+	if block.NumberU64() != bc.CurrentBlock().NumberU64()+1 {
+		utils.Logger().Debug().
+			Uint64("curBlockNum", bc.CurrentBlock().NumberU64()).
+			Uint64("receivedBlockNum", block.NumberU64()).
+			Msg("[STAGED_STREAM_SYNC] Inappropriate block number, ignore!")
+		return nil
+	}
+
+	haveCurrentSig := len(block.GetCurrentCommitSig()) != 0
+	// Verify block signatures
+	if block.NumberU64() > 1 {
+		// Verify signature every N blocks (which N is verifyHeaderBatchSize and can be adjusted in configs)
+		verifySeal := block.NumberU64()%VerifyHeaderBatchSize == 0 || verifyAllSig
+		verifyCurrentSig := verifyAllSig && haveCurrentSig
+		if verifyCurrentSig {
+			sig, bitmap, err := chain.ParseCommitSigAndBitmap(block.GetCurrentCommitSig())
+			if err != nil {
+				return errors.Wrap(err, "parse commitSigAndBitmap")
+			}
+
+			startTime := time.Now()
+			if err := bc.Engine().VerifyHeaderSignature(bc, block.Header(), sig, bitmap); err != nil {
+				return errors.Wrapf(err, "verify header signature %v", block.Hash().String())
+			}
+			utils.Logger().Debug().
+				Int64("elapsed time", time.Now().Sub(startTime).Milliseconds()).
+				Msg("[STAGED_STREAM_SYNC] VerifyHeaderSignature")
+		}
+		err := bc.Engine().VerifyHeader(bc, block.Header(), verifySeal)
+		if err == engine.ErrUnknownAncestor {
+			return nil
+		} else if err != nil {
+			utils.Logger().Error().
+				Err(err).
+				Uint64("block number", block.NumberU64()).
+				Msgf("[STAGED_STREAM_SYNC] UpdateBlockAndStatus: failed verifying signatures for new block")
+			return err
+		}
+	}
+
+	_, err := bc.InsertChain([]*types.Block{block}, false /* verifyHeaders */)
+	if err != nil {
+		utils.Logger().Error().
+			Err(err).
+			Uint64("block number", block.NumberU64()).
+			Uint32("shard", block.ShardID()).
+			Msgf("[STAGED_STREAM_SYNC] UpdateBlockAndStatus: Error adding new block to blockchain")
+		return err
+	}
+	utils.Logger().Info().
+		Uint64("blockHeight", block.NumberU64()).
+		Uint64("blockEpoch", block.Epoch().Uint64()).
+		Str("blockHex", block.Hash().Hex()).
+		Uint32("ShardID", block.ShardID()).
+		Msg("[STAGED_STREAM_SYNC] UpdateBlockAndStatus: New Block Added to Blockchain")
+
+	for i, tx := range block.StakingTransactions() {
+		utils.Logger().Info().Msgf("StakingTxn %d: %s, %v", i, tx.StakingType().String(), tx.StakingMessage())
+	}
+	return nil
+}
diff --git a/api/service/stagedstreamsync/stages.go b/api/service/stagedstreamsync/stages.go
index 55681d68f5..6a21fe7071 100644
--- a/api/service/stagedstreamsync/stages.go
+++ b/api/service/stagedstreamsync/stages.go
@@ -13,6 +13,7 @@ const (
 	SyncEpoch   SyncStageID = "SyncEpoch"   // epoch sync
 	BlockBodies SyncStageID = "BlockBodies" // Block bodies are downloaded, TxHash and UncleHash are getting verified
 	States      SyncStageID = "States"      // will construct most recent state from downloaded blocks
+	LastMile    SyncStageID = "LastMile"    // update blocks after sync and update last mile blocks as well
 	Finish      SyncStageID = "Finish"      // Nominal stage after all other stages
 )
 
diff --git a/api/service/stagedstreamsync/syncing.go b/api/service/stagedstreamsync/syncing.go
index ebef810b19..738f2f9203 100644
--- a/api/service/stagedstreamsync/syncing.go
+++ b/api/service/stagedstreamsync/syncing.go
@@ -4,13 +4,15 @@ import (
 	"context"
 	"fmt"
 	"path/filepath"
+	"runtime"
+	"strings"
 	"sync"
 	"time"
 
+	"github.com/harmony-one/harmony/consensus"
 	"github.com/harmony-one/harmony/core"
 	"github.com/harmony-one/harmony/internal/utils"
 	sttypes "github.com/harmony-one/harmony/p2p/stream/types"
-	"github.com/harmony-one/harmony/shard"
 	"github.com/ledgerwatch/erigon-lib/kv"
 	"github.com/ledgerwatch/erigon-lib/kv/mdbx"
 	"github.com/ledgerwatch/erigon-lib/kv/memdb"
@@ -38,41 +40,53 @@ var Buckets = []string{
 // CreateStagedSync creates an instance of staged sync
 func CreateStagedSync(ctx context.Context,
 	bc core.BlockChain,
+	consensus *consensus.Consensus,
 	dbDir string,
-	UseMemDB bool,
 	isBeaconNode bool,
 	protocol syncProtocol,
 	config Config,
 	logger zerolog.Logger,
-	logProgress bool,
 ) (*StagedStreamSync, error) {
 
-	isBeacon := bc.ShardID() == shard.BeaconChainShardID
+	logger.Info().
+		Uint32("shard", bc.ShardID()).
+		Bool("beaconNode", isBeaconNode).
+		Bool("memdb", config.UseMemDB).
+		Str("dbDir", dbDir).
+		Bool("serverOnly", config.ServerOnly).
+		Int("minStreams", config.MinStreams).
+		Msg(WrapStagedSyncMsg("creating staged sync"))
 
 	var mainDB kv.RwDB
 	dbs := make([]kv.RwDB, config.Concurrency)
-	if UseMemDB {
-		mainDB = memdb.New(getMemDbTempPath(dbDir, -1))
+	if config.UseMemDB {
+		mainDB = memdb.New(getBlockDbPath(bc.ShardID(), isBeaconNode, -1, dbDir))
 		for i := 0; i < config.Concurrency; i++ {
-			dbs[i] = memdb.New(getMemDbTempPath(dbDir, i))
+			dbPath := getBlockDbPath(bc.ShardID(), isBeaconNode, i, dbDir)
+			dbs[i] = memdb.New(dbPath)
 		}
 	} else {
-		mainDB = mdbx.NewMDBX(log.New()).Path(getBlockDbPath(isBeacon, -1, dbDir)).MustOpen()
+		logger.Info().
+			Str("path", getBlockDbPath(bc.ShardID(), isBeaconNode, -1, dbDir)).
+			Msg(WrapStagedSyncMsg("creating main db"))
+		mainDB = mdbx.NewMDBX(log.New()).Path(getBlockDbPath(bc.ShardID(), isBeaconNode, -1, dbDir)).MustOpen()
 		for i := 0; i < config.Concurrency; i++ {
-			dbPath := getBlockDbPath(isBeacon, i, dbDir)
+			dbPath := getBlockDbPath(bc.ShardID(), isBeaconNode, i, dbDir)
 			dbs[i] = mdbx.NewMDBX(log.New()).Path(dbPath).MustOpen()
 		}
 	}
 
 	if errInitDB := initDB(ctx, mainDB, dbs, config.Concurrency); errInitDB != nil {
+		logger.Error().Err(errInitDB).Msg("create staged sync instance failed")
 		return nil, errInitDB
 	}
 
 	stageHeadsCfg := NewStageHeadersCfg(bc, mainDB)
 	stageShortRangeCfg := NewStageShortRangeCfg(bc, mainDB)
 	stageSyncEpochCfg := NewStageEpochCfg(bc, mainDB)
-	stageBodiesCfg := NewStageBodiesCfg(bc, mainDB, dbs, config.Concurrency, protocol, isBeacon, logProgress)
-	stageStatesCfg := NewStageStatesCfg(bc, mainDB, dbs, config.Concurrency, logger, logProgress)
+	stageBodiesCfg := NewStageBodiesCfg(bc, mainDB, dbs, config.Concurrency, protocol, isBeaconNode, config.LogProgress)
+	stageStatesCfg := NewStageStatesCfg(bc, mainDB, dbs, config.Concurrency, logger, config.LogProgress)
+	lastMileCfg := NewStageLastMileCfg(ctx, bc, mainDB)
 	stageFinishCfg := NewStageFinishCfg(mainDB)
 
 	stages := DefaultStages(ctx,
@@ -81,17 +95,27 @@ func CreateStagedSync(ctx context.Context,
 		stageShortRangeCfg,
 		stageBodiesCfg,
 		stageStatesCfg,
+		lastMileCfg,
 		stageFinishCfg,
 	)
 
+	logger.Info().
+		Uint32("shard", bc.ShardID()).
+		Bool("beaconNode", isBeaconNode).
+		Bool("memdb", config.UseMemDB).
+		Str("dbDir", dbDir).
+		Bool("serverOnly", config.ServerOnly).
+		Int("minStreams", config.MinStreams).
+		Msg(WrapStagedSyncMsg("staged sync created successfully"))
+
 	return New(
 		bc,
+		consensus,
 		mainDB,
 		stages,
-		isBeacon,
+		isBeaconNode,
 		protocol,
 		isBeaconNode,
-		UseMemDB,
 		config,
 		logger,
 	), nil
@@ -147,7 +171,7 @@ func getMemDbTempPath(dbDir string, dbIndex int) string {
 }
 
 // getBlockDbPath returns the path of the cache database which stores blocks
-func getBlockDbPath(beacon bool, loopID int, dbDir string) string {
+func getBlockDbPath(shardID uint32, beacon bool, loopID int, dbDir string) string {
 	if beacon {
 		if loopID >= 0 {
 			return fmt.Sprintf("%s_%d", filepath.Join(dbDir, "cache/beacon_blocks_db"), loopID)
@@ -156,30 +180,57 @@ func getBlockDbPath(beacon bool, loopID int, dbDir string) string {
 		}
 	} else {
 		if loopID >= 0 {
-			return fmt.Sprintf("%s_%d", filepath.Join(dbDir, "cache/blocks_db"), loopID)
+			return fmt.Sprintf("%s_%d_%d", filepath.Join(dbDir, "cache/blocks_db"), shardID, loopID)
 		} else {
-			return filepath.Join(dbDir, "cache/blocks_db_main")
+			return fmt.Sprintf("%s_%d", filepath.Join(dbDir, "cache/blocks_db_main"), shardID)
 		}
 	}
 }
 
+func (s *StagedStreamSync) Debug(source string, msg interface{}) {
+	// only log the msg in debug mode
+	if !s.config.DebugMode {
+		return
+	}
+	pc, _, _, _ := runtime.Caller(1)
+	caller := runtime.FuncForPC(pc).Name()
+	callerParts := strings.Split(caller, "/")
+	if len(callerParts) > 0 {
+		caller = callerParts[len(callerParts)-1]
+	}
+	src := source
+	if src == "" {
+		src = "message"
+	}
+	// SSSD: STAGED STREAM SYNC DEBUG
+	if msg == nil {
+		fmt.Printf("[SSSD:%s] %s: nil or no error\n", caller, src)
+	} else if err, ok := msg.(error); ok {
+		fmt.Printf("[SSSD:%s] %s: %s\n", caller, src, err.Error())
+	} else if str, ok := msg.(string); ok {
+		fmt.Printf("[SSSD:%s] %s: %s\n", caller, src, str)
+	} else {
+		fmt.Printf("[SSSD:%s] %s: %v\n", caller, src, msg)
+	}
+}
+
 // doSync does the long range sync.
 // One LongRangeSync consists of several iterations.
 // For each iteration, estimate the current block number, then fetch block & insert to blockchain
-func (s *StagedStreamSync) doSync(downloaderContext context.Context, initSync bool) (int, error) {
+func (s *StagedStreamSync) doSync(downloaderContext context.Context, initSync bool) (uint64, int, error) {
 
 	var totalInserted int
 
 	s.initSync = initSync
 
 	if err := s.checkPrerequisites(); err != nil {
-		return 0, err
+		return 0, 0, err
 	}
 
 	var estimatedHeight uint64
 	if initSync {
 		if h, err := s.estimateCurrentNumber(downloaderContext); err != nil {
-			return 0, err
+			return 0, 0, err
 		} else {
 			estimatedHeight = h
 			//TODO: use directly currentCycle var
@@ -187,36 +238,70 @@ func (s *StagedStreamSync) doSync(downloaderContext context.Context, initSync bo
 		}
 		if curBN := s.bc.CurrentBlock().NumberU64(); estimatedHeight <= curBN {
 			s.logger.Info().Uint64("current number", curBN).Uint64("target number", estimatedHeight).
-				Msg(WrapStagedSyncMsg("early return of long range sync"))
-			return 0, nil
+				Msg(WrapStagedSyncMsg("early return of long range sync (chain is already ahead of target height)"))
+			return estimatedHeight, 0, nil
 		}
-
-		s.startSyncing()
-		defer s.finishSyncing()
 	}
 
+	s.startSyncing()
+	defer s.finishSyncing()
+
 	for {
 		ctx, cancel := context.WithCancel(downloaderContext)
 
 		n, err := s.doSyncCycle(ctx, initSync)
 		if err != nil {
+			utils.Logger().Error().
+				Err(err).
+				Bool("initSync", s.initSync).
+				Bool("isBeacon", s.isBeacon).
+				Uint32("shard", s.bc.ShardID()).
+				Msg(WrapStagedSyncMsg("sync cycle failed"))
+
 			pl := s.promLabels()
 			pl["error"] = err.Error()
 			numFailedDownloadCounterVec.With(pl).Inc()
 
 			cancel()
-			return totalInserted + n, err
+			return estimatedHeight, totalInserted + n, err
 		}
 		cancel()
 
 		totalInserted += n
 
 		// if it's not long range sync, skip loop
-		if n < LastMileBlocksThreshold || !initSync {
-			return totalInserted, nil
+		if n == 0 || !initSync {
+			break
+		}
+	}
+
+	if totalInserted > 0 {
+		utils.Logger().Info().
+			Bool("initSync", s.initSync).
+			Bool("isBeacon", s.isBeacon).
+			Uint32("shard", s.bc.ShardID()).
+			Int("blocks", totalInserted).
+			Msg(WrapStagedSyncMsg("sync cycle blocks inserted successfully"))
+	}
+
+	// add consensus last mile blocks
+	if s.consensus != nil {
+		if hashes, err := s.addConsensusLastMile(s.Blockchain(), s.consensus); err != nil {
+			utils.Logger().Error().Err(err).
+				Msg("[STAGED_STREAM_SYNC] Add consensus last mile failed")
+			s.RollbackLastMileBlocks(downloaderContext, hashes)
+			return estimatedHeight, totalInserted, err
+		} else {
+			totalInserted += len(hashes)
+		}
+		// TODO: move this to explorer handler code.
+		if s.isExplorer {
+			s.consensus.UpdateConsensusInformation()
 		}
 	}
+	s.purgeLastMileBlocksFromCache()
 
+	return estimatedHeight, totalInserted, nil
 }
 
 func (s *StagedStreamSync) doSyncCycle(ctx context.Context, initSync bool) (int, error) {
diff --git a/api/service/stagedsync/stagedsync.go b/api/service/stagedsync/stagedsync.go
index 83af6abf9f..f1de66f9fc 100644
--- a/api/service/stagedsync/stagedsync.go
+++ b/api/service/stagedsync/stagedsync.go
@@ -83,6 +83,9 @@ type StagedSync struct {
 	StagedSyncTurboMode bool
 	// log the full sync progress in console
 	LogProgress bool
+	// log every single process and error to help to debug the syncing
+	// DebugMode is not accessible to the end user and is only an aid for development
+	DebugMode bool
 }
 
 // BlockWithSig the serialization structure for request DownloaderRequest_BLOCKWITHSIG
@@ -258,7 +261,8 @@ func New(ctx context.Context,
 	verifyAllSig bool,
 	verifyHeaderBatchSize uint64,
 	insertChainBatchSize int,
-	logProgress bool) *StagedSync {
+	logProgress bool,
+	debugMode bool) *StagedSync {
 
 	revertStages := make([]*Stage, len(stagesList))
 	for i, stageIndex := range revertOrder {
@@ -312,6 +316,7 @@ func New(ctx context.Context,
 		VerifyHeaderBatchSize:  verifyHeaderBatchSize,
 		InsertChainBatchSize:   insertChainBatchSize,
 		LogProgress:            logProgress,
+		DebugMode:              debugMode,
 	}
 }
 
diff --git a/api/service/stagedsync/syncing.go b/api/service/stagedsync/syncing.go
index 11147f6a62..a22a4e9253 100644
--- a/api/service/stagedsync/syncing.go
+++ b/api/service/stagedsync/syncing.go
@@ -64,6 +64,7 @@ func CreateStagedSync(
 	verifyHeaderBatchSize uint64,
 	insertChainBatchSize int,
 	logProgress bool,
+	debugMode bool,
 ) (*StagedSync, error) {
 
 	ctx := context.Background()
@@ -134,6 +135,7 @@ func CreateStagedSync(
 		verifyHeaderBatchSize,
 		insertChainBatchSize,
 		logProgress,
+		debugMode,
 	), nil
 }
 
diff --git a/cmd/harmony/default.go b/cmd/harmony/default.go
index 38ae3dacbb..4cc20cfdf4 100644
--- a/cmd/harmony/default.go
+++ b/cmd/harmony/default.go
@@ -178,6 +178,7 @@ var defaultStagedSyncConfig = harmonyconfig.StagedSyncConfig{
 	MaxMemSyncCycleSize:    1024,  // max number of blocks to use a single transaction for staged sync
 	UseMemDB:               true,  // it uses memory by default. set it to false to use disk
 	LogProgress:            false, // log the full sync progress in console
+	DebugMode:              false, // log every single process and error to help to debug the syncing (DebugMode is not accessible to the end user and is only an aid for development)
 }
 
 var (
diff --git a/cmd/harmony/main.go b/cmd/harmony/main.go
index e66d3c9c73..16f985beac 100644
--- a/cmd/harmony/main.go
+++ b/cmd/harmony/main.go
@@ -606,6 +606,7 @@ func createGlobalConfig(hc harmonyconfig.HarmonyConfig) (*nodeconfig.ConfigType,
 	nodeConfig.VerifyHeaderBatchSize = hc.Sync.StagedSyncCfg.VerifyHeaderBatchSize
 	nodeConfig.InsertChainBatchSize = hc.Sync.StagedSyncCfg.InsertChainBatchSize
 	nodeConfig.LogProgress = hc.Sync.StagedSyncCfg.LogProgress
+	nodeConfig.DebugMode = hc.Sync.StagedSyncCfg.DebugMode
 	// P2P private key is used for secure message transfer between p2p nodes.
 	nodeConfig.P2PPriKey, _, err = utils.LoadKeyFromFile(hc.P2P.KeyFile)
 	if err != nil {
@@ -942,7 +943,9 @@ func setupStagedSyncService(node *node.Node, host p2p.Host, hc harmonyconfig.Har
 		SmHardLowCap:         hc.Sync.DiscHardLowCap,
 		SmHiCap:              hc.Sync.DiscHighCap,
 		SmDiscBatch:          hc.Sync.DiscBatch,
-		LogProgress:          node.NodeConfig.LogProgress,
+		UseMemDB:             hc.Sync.StagedSyncCfg.UseMemDB,
+		LogProgress:          hc.Sync.StagedSyncCfg.LogProgress,
+		DebugMode:            hc.Sync.StagedSyncCfg.DebugMode,
 	}
 
 	// If we are running side chain, we will need to do some extra works for beacon
@@ -954,7 +957,7 @@ func setupStagedSyncService(node *node.Node, host p2p.Host, hc harmonyconfig.Har
 		}
 	}
 	//Setup stream sync service
-	s := stagedstreamsync.NewService(host, blockchains, sConfig, hc.General.DataDir)
+	s := stagedstreamsync.NewService(host, blockchains, node.Consensus, sConfig, hc.General.DataDir)
 
 	node.RegisterService(service.StagedStreamSync, s)
 
diff --git a/consensus/consensus_v2.go b/consensus/consensus_v2.go
index 38bb06ff4a..3627f0b658 100644
--- a/consensus/consensus_v2.go
+++ b/consensus/consensus_v2.go
@@ -157,10 +157,11 @@ func (consensus *Consensus) finalCommit() {
 			Msg("[finalCommit] Unable to construct Committed message")
 		return
 	}
-	msgToSend, FBFTMsg :=
-		network.Bytes,
-		network.FBFTMsg
-	commitSigAndBitmap := FBFTMsg.Payload
+	var (
+		msgToSend          = network.Bytes
+		FBFTMsg            = network.FBFTMsg
+		commitSigAndBitmap = FBFTMsg.Payload
+	)
 	consensus.fBFTLog.AddVerifiedMessage(FBFTMsg)
 	// find correct block content
 	curBlockHash := consensus.blockHash
diff --git a/consensus/validator.go b/consensus/validator.go
index ee30d8c006..0506f4359d 100644
--- a/consensus/validator.go
+++ b/consensus/validator.go
@@ -132,7 +132,7 @@ func (consensus *Consensus) validateNewBlock(recvMsg *FBFTMessage) (*types.Block
 
 	if err := consensus.verifyBlock(&blockObj); err != nil {
 		consensus.getLogger().Error().Err(err).Msg("[validateNewBlock] Block verification failed")
-		return nil, errors.New("Block verification failed")
+		return nil, errors.Errorf("Block verification failed: %s", err.Error())
 	}
 	return &blockObj, nil
 }
diff --git a/core/blockchain_impl.go b/core/blockchain_impl.go
index 698eaeebac..965dccd9a4 100644
--- a/core/blockchain_impl.go
+++ b/core/blockchain_impl.go
@@ -221,6 +221,7 @@ type BlockChainImpl struct {
 	badBlocks              *lru.Cache // Bad block cache
 	pendingSlashes         slash.Records
 	maxGarbCollectedBlkNum int64
+	leaderRotationMeta     leaderRotationMeta
 
 	options Options
 }
@@ -359,6 +360,12 @@ func newBlockChainWithOptions(
 		bc.snaps, _ = snapshot.New(snapconfig, bc.db, bc.triedb, head.Hash())
 	}
 
+	curHeader := bc.CurrentBlock().Header()
+	err = bc.buildLeaderRotationMeta(curHeader)
+	if err != nil {
+		return nil, errors.WithMessage(err, "failed to build leader rotation meta")
+	}
+
 	// Take ownership of this particular state
 	go bc.update()
 	return bc, nil
@@ -1479,8 +1486,11 @@ func (bc *BlockChainImpl) WriteBlockWithState(
 	defer bc.mu.Unlock()
 
 	currentBlock := bc.CurrentBlock()
-	if currentBlock == nil || block.ParentHash() != currentBlock.Hash() {
-		return NonStatTy, errors.New("Hash of parent block doesn't match the current block hash")
+	if currentBlock == nil {
+		return NonStatTy, errors.New("Current block is nil")
+	}
+	if block.ParentHash() != currentBlock.Hash() {
+		return NonStatTy, errors.Errorf("Hash of parent block %s doesn't match the current block hash %s", currentBlock.Hash().Hex(), block.ParentHash().Hex())
 	}
 
 	// Commit state object changes to in-memory trie
@@ -1650,20 +1660,52 @@ func (bc *BlockChainImpl) InsertChain(chain types.Blocks, verifyHeaders bool) (i
 	return n, err
 }
 
+// buildLeaderRotationMeta builds leader rotation meta if feature is activated.
+func (bc *BlockChainImpl) buildLeaderRotationMeta(curHeader *block.Header) error {
+	if !bc.chainConfig.IsLeaderRotation(curHeader.Epoch()) {
+		return nil
+	}
+	if curHeader.NumberU64() == 0 {
+		return errors.New("current header is genesis")
+	}
+	curPubKey, err := bc.getLeaderPubKeyFromCoinbase(curHeader)
+	if err != nil {
+		return err
+	}
+	for i := curHeader.NumberU64() - 1; i >= 0; i-- {
+		header := bc.GetHeaderByNumber(i)
+		if header == nil {
+			return errors.New("header is nil")
+		}
+		blockPubKey, err := bc.getLeaderPubKeyFromCoinbase(header)
+		if err != nil {
+			return err
+		}
+		if curPubKey.Bytes != blockPubKey.Bytes || curHeader.Epoch().Uint64() != header.Epoch().Uint64() {
+			for j := i; i <= curHeader.NumberU64(); j++ {
+				header := bc.GetHeaderByNumber(i)
+				if header == nil {
+					return errors.New("header is nil")
+				}
+				err := bc.saveLeaderRotationMeta(header)
+				if err != nil {
+					utils.Logger().Error().Err(err).Msg("save leader continuous blocks count error")
+					return err
+				}
+			}
+			return nil
+		}
+	}
+	return errors.New("no leader rotation meta to save")
+}
+
 func (bc *BlockChainImpl) saveLeaderRotationMeta(h *block.Header) error {
 	blockPubKey, err := bc.getLeaderPubKeyFromCoinbase(h)
 	if err != nil {
 		return err
 	}
-	type stored struct {
-		pub    []byte
-		epoch  uint64
-		count  uint64
-		shifts uint64
-	}
-	var s stored
-	// error is possible here only on the first iteration, so we can ignore it
-	s.pub, s.epoch, s.count, s.shifts, _ = rawdb.ReadLeaderRotationMeta(bc.db)
+
+	var s = bc.leaderRotationMeta
 
 	// increase counter only if the same leader and epoch
 	if bytes.Equal(s.pub, blockPubKey.Bytes[:]) && s.epoch == h.Epoch().Uint64() {
@@ -1679,11 +1721,9 @@ func (bc *BlockChainImpl) saveLeaderRotationMeta(h *block.Header) error {
 	if s.epoch != h.Epoch().Uint64() {
 		s.shifts = 0
 	}
+	s.epoch = h.Epoch().Uint64()
+	bc.leaderRotationMeta = s
 
-	err = rawdb.WriteLeaderRotationMeta(bc.db, blockPubKey.Bytes[:], h.Epoch().Uint64(), s.count, s.shifts)
-	if err != nil {
-		return err
-	}
 	return nil
 }
 
diff --git a/core/blockchain_leader_rotation.go b/core/blockchain_leader_rotation.go
new file mode 100644
index 0000000000..6b9c91a927
--- /dev/null
+++ b/core/blockchain_leader_rotation.go
@@ -0,0 +1,8 @@
+package core
+
+type leaderRotationMeta struct {
+	pub    []byte
+	epoch  uint64
+	count  uint64
+	shifts uint64
+}
diff --git a/core/state_processor.go b/core/state_processor.go
index fe7eeffd12..7a2f2a5d47 100644
--- a/core/state_processor.go
+++ b/core/state_processor.go
@@ -119,8 +119,8 @@ func (p *StateProcessor) Process(
 		usedGas        = new(uint64)
 		header         = block.Header()
 		allLogs        []*types.Log
-		gp                                = new(GasPool).AddGas(block.GasLimit())
-		blockStakeMsgs []staking.StakeMsg = make([]staking.StakeMsg, 0)
+		gp             = new(GasPool).AddGas(block.GasLimit())
+		blockStakeMsgs = make([]staking.StakeMsg, 0)
 	)
 
 	beneficiary, err := p.bc.GetECDSAFromCoinbase(header)
@@ -202,7 +202,7 @@ func (p *StateProcessor) Process(
 		receipts, outcxs, incxs, block.StakingTransactions(), slashes, sigsReady, func() uint64 { return header.ViewID().Uint64() },
 	)
 	if err != nil {
-		return nil, nil, nil, nil, 0, nil, statedb, errors.New("[Process] Cannot finalize block")
+		return nil, nil, nil, nil, 0, nil, statedb, errors.WithMessage(err, "[Process] Cannot finalize block")
 	}
 
 	result := &ProcessorResult{
diff --git a/core_test/shardchain_test.go b/core_test/shardchain_test.go
new file mode 100644
index 0000000000..36a32f5433
--- /dev/null
+++ b/core_test/shardchain_test.go
@@ -0,0 +1,83 @@
+package core_test
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/harmony-one/harmony/consensus"
+	"github.com/harmony-one/harmony/consensus/quorum"
+	"github.com/harmony-one/harmony/core"
+	"github.com/harmony-one/harmony/core/types"
+	"github.com/harmony-one/harmony/crypto/bls"
+	"github.com/harmony-one/harmony/internal/chain"
+	nodeconfig "github.com/harmony-one/harmony/internal/configs/node"
+	"github.com/harmony-one/harmony/internal/registry"
+	"github.com/harmony-one/harmony/internal/shardchain"
+	"github.com/harmony-one/harmony/internal/utils"
+	"github.com/harmony-one/harmony/multibls"
+	"github.com/harmony-one/harmony/node"
+	"github.com/harmony-one/harmony/p2p"
+	"github.com/harmony-one/harmony/shard"
+	"github.com/stretchr/testify/require"
+)
+
+var testDBFactory = &shardchain.MemDBFactory{}
+
+func TestAddNewBlock(t *testing.T) {
+	blsKey := bls.RandPrivateKey()
+	pubKey := blsKey.GetPublicKey()
+	leader := p2p.Peer{IP: "127.0.0.1", Port: "9882", ConsensusPubKey: pubKey}
+	priKey, _, _ := utils.GenKeyP2P("127.0.0.1", "9902")
+	host, err := p2p.NewHost(p2p.HostConfig{
+		Self:   &leader,
+		BLSKey: priKey,
+	})
+	if err != nil {
+		t.Fatalf("newhost failure: %v", err)
+	}
+	engine := chain.NewEngine()
+	chainconfig := nodeconfig.GetShardConfig(shard.BeaconChainShardID).GetNetworkType().ChainConfig()
+	collection := shardchain.NewCollection(
+		nil, testDBFactory, &core.GenesisInitializer{NetworkType: nodeconfig.GetShardConfig(shard.BeaconChainShardID).GetNetworkType()}, engine, &chainconfig,
+	)
+	decider := quorum.NewDecider(
+		quorum.SuperMajorityVote, shard.BeaconChainShardID,
+	)
+	blockchain, err := collection.ShardChain(shard.BeaconChainShardID)
+	if err != nil {
+		t.Fatal("cannot get blockchain")
+	}
+	reg := registry.New().SetBlockchain(blockchain)
+	consensus, err := consensus.New(
+		host, shard.BeaconChainShardID, multibls.GetPrivateKeys(blsKey), reg, decider, 3, false,
+	)
+	if err != nil {
+		t.Fatalf("Cannot craeate consensus: %v", err)
+	}
+	nodeconfig.SetNetworkType(nodeconfig.Testnet)
+	var block *types.Block
+	node := node.New(host, consensus, engine, collection, nil, nil, nil, nil, nil, reg)
+	commitSigs := make(chan []byte, 1)
+	commitSigs <- []byte{}
+	block, err = node.Worker.FinalizeNewBlock(
+		commitSigs, func() uint64 { return uint64(0) }, common.Address{}, nil, nil,
+	)
+	if err != nil {
+		t.Fatal("cannot finalize new block")
+	}
+
+	nn := node.Blockchain().CurrentBlock()
+	t.Log("[*]", nn.NumberU64(), nn.Hash().Hex(), nn.ParentHash())
+
+	_, err = blockchain.InsertChain([]*types.Block{block}, false)
+	require.NoError(t, err, "error when adding new block")
+
+	pk, epoch, count, shifts, err := blockchain.LeaderRotationMeta()
+	fmt.Println("pk", pk, "epoch", epoch, "count", count, "shifts", shifts, "err", err)
+
+	t.Log("#", block.Header().NumberU64(), node.Blockchain().CurrentBlock().NumberU64(), block.Hash().Hex(), block.ParentHash())
+
+	err = blockchain.Rollback([]common.Hash{block.Hash()})
+	require.NoError(t, err, "error when rolling back")
+}
diff --git a/internal/configs/harmony/harmony.go b/internal/configs/harmony/harmony.go
index f4f2ddb96f..5aca663a89 100644
--- a/internal/configs/harmony/harmony.go
+++ b/internal/configs/harmony/harmony.go
@@ -343,6 +343,7 @@ type StagedSyncConfig struct {
 	VerifyHeaderBatchSize  uint64 // batch size to verify header before insert to chain
 	UseMemDB               bool   // it uses memory by default. set it to false to use disk
 	LogProgress            bool   // log the full sync progress in console
+	DebugMode              bool   // log every single process and error to help to debug syncing issues (DebugMode is not accessible to the end user and is only an aid for development)
 }
 
 type PriceLimit int64
diff --git a/internal/configs/node/config.go b/internal/configs/node/config.go
index 9f681fca9f..5370a2e52f 100644
--- a/internal/configs/node/config.go
+++ b/internal/configs/node/config.go
@@ -58,6 +58,31 @@ const (
 	Localnet  = "localnet"
 )
 
+// ChainConfig returns the chain configuration for the network type.
+func (t NetworkType) ChainConfig() params.ChainConfig {
+	switch t {
+	case Mainnet:
+		return *params.MainnetChainConfig
+	case Pangaea:
+		return *params.PangaeaChainConfig
+	case Partner:
+		return *params.PartnerChainConfig
+	case Stressnet:
+		return *params.StressnetChainConfig
+	case Localnet:
+		return *params.LocalnetChainConfig
+	default:
+		return *params.TestnetChainConfig
+	}
+}
+
+func (n NetworkType) String() string {
+	if n == "" {
+		return Testnet // default to testnet
+	}
+	return string(n)
+}
+
 // Global is the index of the global node configuration
 const (
 	Global    = 0
@@ -93,6 +118,7 @@ type ConfigType struct {
 	VerifyAllSig           bool   // verify signatures for all blocks regardless of height and batch size
 	VerifyHeaderBatchSize  uint64 // batch size to verify header before insert to chain
 	LogProgress            bool   // log the full sync progress in console
+	DebugMode              bool   // log every single process and error to help to debug the syncing issues
 	NtpServer              string
 	StringRole             string
 	P2PPriKey              p2p_crypto.PrivKey   `json:"-"`
@@ -351,21 +377,3 @@ func (conf *ConfigType) ValidateConsensusKeysForSameShard(pubkeys multibls.Publi
 	}
 	return nil
 }
-
-// ChainConfig returns the chain configuration for the network type.
-func (t NetworkType) ChainConfig() params.ChainConfig {
-	switch t {
-	case Mainnet:
-		return *params.MainnetChainConfig
-	case Pangaea:
-		return *params.PangaeaChainConfig
-	case Partner:
-		return *params.PartnerChainConfig
-	case Stressnet:
-		return *params.StressnetChainConfig
-	case Localnet:
-		return *params.LocalnetChainConfig
-	default:
-		return *params.TestnetChainConfig
-	}
-}
diff --git a/node/node_handler_test.go b/node/node_handler_test.go
index 3de2918398..307e21b11a 100644
--- a/node/node_handler_test.go
+++ b/node/node_handler_test.go
@@ -46,13 +46,11 @@ func TestAddNewBlock(t *testing.T) {
 		t.Fatal("cannot get blockchain")
 	}
 	reg := registry.New().SetBlockchain(blockchain)
-	consensus, err := consensus.New(
-		host, shard.BeaconChainShardID, multibls.GetPrivateKeys(blsKey), reg, decider, 3, false,
-	)
+	consensus, err := consensus.New(host, shard.BeaconChainShardID, multibls.GetPrivateKeys(blsKey), reg, decider, 3, false)
 	if err != nil {
 		t.Fatalf("Cannot craeate consensus: %v", err)
 	}
-	nodeconfig.SetNetworkType(nodeconfig.Devnet)
+	nodeconfig.SetNetworkType(nodeconfig.Testnet)
 	node := New(host, consensus, engine, collection, nil, nil, nil, nil, nil, reg)
 
 	txs := make(map[common.Address]types.Transactions)
diff --git a/node/node_newblock_test.go b/node/node_newblock_test.go
index 39affacaba..963af2f55b 100644
--- a/node/node_newblock_test.go
+++ b/node/node_newblock_test.go
@@ -63,10 +63,8 @@ func TestFinalizeNewBlockAsync(t *testing.T) {
 	node.Worker.CommitTransactions(
 		txs, stks, common.Address{},
 	)
-	commitSigs := make(chan []byte)
-	go func() {
-		commitSigs <- []byte{}
-	}()
+	commitSigs := make(chan []byte, 1)
+	commitSigs <- []byte{}
 
 	block, _ := node.Worker.FinalizeNewBlock(
 		commitSigs, func() uint64 { return 0 }, common.Address{}, nil, nil,
diff --git a/node/node_syncing.go b/node/node_syncing.go
index 84eb1256ff..68c3338362 100644
--- a/node/node_syncing.go
+++ b/node/node_syncing.go
@@ -122,7 +122,8 @@ func (node *Node) createStagedSync(bc core.BlockChain) *stagedsync.StagedSync {
 		node.NodeConfig.VerifyAllSig,
 		node.NodeConfig.VerifyHeaderBatchSize,
 		node.NodeConfig.InsertChainBatchSize,
-		node.NodeConfig.LogProgress); err != nil {
+		node.NodeConfig.LogProgress,
+		node.NodeConfig.DebugMode); err != nil {
 		return nil
 	} else {
 		return s
@@ -352,7 +353,7 @@ func (node *Node) NodeSyncing() {
 		if node.HarmonyConfig.TiKV.Role == tikv.RoleWriter {
 			node.supportSyncing() // the writer needs to be in sync with it's other peers
 		}
-	} else if !node.HarmonyConfig.General.IsOffline && node.HarmonyConfig.DNSSync.Client {
+	} else if !node.HarmonyConfig.General.IsOffline && (node.HarmonyConfig.DNSSync.Client || node.HarmonyConfig.Sync.Downloader) {
 		node.supportSyncing() // for non-writer-reader mode a.k.a tikv nodes
 	}
 }
@@ -372,6 +373,11 @@ func (node *Node) supportSyncing() {
 		go node.SendNewBlockToUnsync()
 	}
 
+	// if stream sync client is running, don't create other sync client instances
+	if node.HarmonyConfig.Sync.Downloader {
+		return
+	}
+
 	if !node.NodeConfig.StagedSync && node.stateSync == nil {
 		node.stateSync = node.createStateSync(node.Blockchain())
 		utils.Logger().Debug().Msg("[SYNC] initialized state sync")
diff --git a/p2p/host.go b/p2p/host.go
index 9395e1df45..246b598b22 100644
--- a/p2p/host.go
+++ b/p2p/host.go
@@ -12,17 +12,17 @@ import (
 	"time"
 
 	"github.com/libp2p/go-libp2p"
-	"github.com/libp2p/go-libp2p-core/host"
-	"github.com/libp2p/go-libp2p-core/routing"
 	dht "github.com/libp2p/go-libp2p-kad-dht"
 	libp2p_pubsub "github.com/libp2p/go-libp2p-pubsub"
 	libp2p_config "github.com/libp2p/go-libp2p/config"
 	libp2p_crypto "github.com/libp2p/go-libp2p/core/crypto"
+	"github.com/libp2p/go-libp2p/core/host"
 	libp2p_host "github.com/libp2p/go-libp2p/core/host"
 	libp2p_network "github.com/libp2p/go-libp2p/core/network"
 	libp2p_peer "github.com/libp2p/go-libp2p/core/peer"
 	libp2p_peerstore "github.com/libp2p/go-libp2p/core/peerstore"
 	"github.com/libp2p/go-libp2p/core/protocol"
+	"github.com/libp2p/go-libp2p/core/routing"
 	"github.com/libp2p/go-libp2p/p2p/net/connmgr"
 
 	"github.com/libp2p/go-libp2p/p2p/security/noise"
diff --git a/p2p/stream/protocols/sync/protocol.go b/p2p/stream/protocols/sync/protocol.go
index 3dcbd6f063..ca4590c972 100644
--- a/p2p/stream/protocols/sync/protocol.go
+++ b/p2p/stream/protocols/sync/protocol.go
@@ -2,7 +2,6 @@ package sync
 
 import (
 	"context"
-	"fmt"
 	"strconv"
 	"time"
 
@@ -180,7 +179,8 @@ func (p *Protocol) HandleStream(raw libp2p_network.Stream) {
 			Msg("failed to add new stream")
 		return
 	}
-	fmt.Println("Connected to", raw.Conn().RemotePeer().String(), "(", st.ProtoID(), ")", "my ID: ", raw.Conn().LocalPeer().String())
+	//to get my ID use raw.Conn().LocalPeer().String()
+	p.logger.Info().Msgf("Connected to %s (%s)", raw.Conn().RemotePeer().String(), st.ProtoID())
 	st.run()
 }
 
diff --git a/p2p/stream/types/utils.go b/p2p/stream/types/utils.go
index c27d95d60f..72838222b4 100644
--- a/p2p/stream/types/utils.go
+++ b/p2p/stream/types/utils.go
@@ -11,7 +11,7 @@ import (
 
 	nodeconfig "github.com/harmony-one/harmony/internal/configs/node"
 	"github.com/hashicorp/go-version"
-	libp2p_proto "github.com/libp2p/go-libp2p-core/protocol"
+	libp2p_proto "github.com/libp2p/go-libp2p/core/protocol"
 	"github.com/pkg/errors"
 )
 
diff --git a/scripts/travis_go_checker.sh b/scripts/travis_go_checker.sh
index 70638377a5..c6c7640caf 100755
--- a/scripts/travis_go_checker.sh
+++ b/scripts/travis_go_checker.sh
@@ -84,7 +84,7 @@ fi
 echo "Running go test..."
 # Fix https://github.com/golang/go/issues/44129#issuecomment-788351567
 go get -t ./...
-if go test -v -count=1 -vet=all -race ./...
+if go test -count=1 -vet=all -race ./...
 then
 	echo "go test succeeded."
 else