Fix eth events query and sync inconsistent state

- kvdb - Fix path in Last when doing `setNew` - Only close if db != nil, and after closing, always set db to nil - This will avoid a panic in the case where the db is closed but there's an error soon after, and a future call tries to close again. This is because pebble.Close() will panic if the db is already closed. - Avoid calling pebble methods when a the Storage interface already implements that method (like Close). - statedb - In test, avoid calling KVDB method if the same method is available for the StateDB (like MakeCheckpoint, CurrentBatch). - eth - In *EventByBlock methods, take blockHash as input argument and use it when querying the event logs. Previously the blockHash was only taken from the logs results *only if* there was any log. This caused the following issue: if there was no logs, it was not possible to know if the result was from the expected block or an uncle block! By querying logs by blockHash we make sure that even if there are no logs, they are from the right block. - Note that now the function can either be called with a blockNum or blockHash, but not both at the same time. - sync - If there's an error during call to Sync call resetState, which internally resets the stateDB to avoid stale checkpoints (and a corresponding invalid increase in the StateDB batchNum). - During a Sync, after very batch processed, make sure that the StateDB currentBatch corresponds to the batchNum in the smart contract log/event.
2026-02-06 19:06:42 +01:00 · 2021-02-05 13:28:14 +01:00
parent 56d05ce57a
commit 6260dfedad
12 changed files with 300 additions and 217 deletions
--- a/db/kvdb/kvdb.go
+++ b/db/kvdb/kvdb.go
@@ -61,13 +61,13 @@ func (k *Last) setNew() error {
 	defer k.rw.Unlock()
 	if k.db != nil {
 		k.db.Close()
+		k.db = nil
 	}
 	lastPath := path.Join(k.path, PathLast)
-	err := os.RemoveAll(lastPath)
-	if err != nil {
+	if err := os.RemoveAll(lastPath); err != nil {
 		return tracerr.Wrap(err)
 	}
-	db, err := pebble.NewPebbleStorage(path.Join(k.path, lastPath), false)
+	db, err := pebble.NewPebbleStorage(lastPath, false)
 	if err != nil {
 		return tracerr.Wrap(err)
 	}
@@ -80,6 +80,7 @@ func (k *Last) set(kvdb *KVDB, batchNum common.BatchNum) error {
 	defer k.rw.Unlock()
 	if k.db != nil {
 		k.db.Close()
+		k.db = nil
 	}
 	lastPath := path.Join(k.path, PathLast)
 	if err := kvdb.MakeCheckpointFromTo(batchNum, lastPath); err != nil {
@@ -96,7 +97,10 @@ func (k *Last) set(kvdb *KVDB, batchNum common.BatchNum) error {
 func (k *Last) close() {
 	k.rw.Lock()
 	defer k.rw.Unlock()
-	k.db.Close()
+	if k.db != nil {
+		k.db.Close()
+		k.db = nil
+	}
 }

 // NewKVDB creates a new KVDB, allowing to use an in-memory or in-disk storage.
@@ -166,14 +170,12 @@ func (kvdb *KVDB) Reset(batchNum common.BatchNum) error {
 func (kvdb *KVDB) reset(batchNum common.BatchNum, closeCurrent bool) error {
 	currentPath := path.Join(kvdb.path, PathCurrent)

-	if closeCurrent {
-		if err := kvdb.db.Pebble().Close(); err != nil {
-			return tracerr.Wrap(err)
-		}
+	if closeCurrent && kvdb.db != nil {
+		kvdb.db.Close()
+		kvdb.db = nil
 	}
 	// remove 'current'
-	err := os.RemoveAll(currentPath)
-	if err != nil {
+	if err := os.RemoveAll(currentPath); err != nil {
 		return tracerr.Wrap(err)
 	}
 	// remove all checkpoints > batchNum
@@ -249,13 +251,13 @@ func (kvdb *KVDB) ResetFromSynchronizer(batchNum common.BatchNum, synchronizerKV
 	}

 	currentPath := path.Join(kvdb.path, PathCurrent)
-	if err := kvdb.db.Pebble().Close(); err != nil {
-		return tracerr.Wrap(err)
+	if kvdb.db != nil {
+		kvdb.db.Close()
+		kvdb.db = nil
 	}

 	// remove 'current'
-	err := os.RemoveAll(currentPath)
-	if err != nil {
+	if err := os.RemoveAll(currentPath); err != nil {
 		return tracerr.Wrap(err)
 	}
 	// remove all checkpoints
@@ -394,8 +396,7 @@ func (kvdb *KVDB) MakeCheckpoint() error {

 	// if checkpoint BatchNum already exist in disk, delete it
 	if _, err := os.Stat(checkpointPath); !os.IsNotExist(err) {
-		err := os.RemoveAll(checkpointPath)
-		if err != nil {
+		if err := os.RemoveAll(checkpointPath); err != nil {
 			return tracerr.Wrap(err)
 		}
 	} else if err != nil && !os.IsNotExist(err) {
@@ -501,8 +502,7 @@ func (kvdb *KVDB) MakeCheckpointFromTo(fromBatchNum common.BatchNum, dest string
 func pebbleMakeCheckpoint(source, dest string) error {
 	// Remove dest folder (if it exists) before doing the checkpoint
 	if _, err := os.Stat(dest); !os.IsNotExist(err) {
-		err := os.RemoveAll(dest)
-		if err != nil {
+		if err := os.RemoveAll(dest); err != nil {
 			return tracerr.Wrap(err)
 		}
 	} else if err != nil && !os.IsNotExist(err) {
@@ -513,12 +513,7 @@ func pebbleMakeCheckpoint(source, dest string) error {
 	if err != nil {
 		return tracerr.Wrap(err)
 	}
-	defer func() {
-		errClose := sto.Pebble().Close()
-		if errClose != nil {
-			log.Errorw("Pebble.Close", "err", errClose)
-		}
-	}()
+	defer sto.Close()

 	// execute Checkpoint
 	err = sto.Pebble().Checkpoint(dest)
@@ -531,6 +526,9 @@ func pebbleMakeCheckpoint(source, dest string) error {

 // Close the DB
 func (kvdb *KVDB) Close() {
-	kvdb.db.Close()
+	if kvdb.db != nil {
+		kvdb.db.Close()
+		kvdb.db = nil
+	}
 	kvdb.last.close()
 }
--- a/db/statedb/statedb.go
+++ b/db/statedb/statedb.go
@@ -230,8 +230,8 @@ func (s *StateDB) SetCurrentIdx(idx common.Idx) error {
 // those checkpoints will remain in the storage, and eventually will be
 // deleted when MakeCheckpoint overwrites them.
 func (s *StateDB) Reset(batchNum common.BatchNum) error {
-	err := s.db.Reset(batchNum)
-	if err != nil {
+	log.Debugw("Making StateDB Reset", "batch", batchNum, "type", s.Typ)
+	if err := s.db.Reset(batchNum); err != nil {
 		return tracerr.Wrap(err)
 	}
 	if s.MT != nil {
@@ -242,7 +242,6 @@ func (s *StateDB) Reset(batchNum common.BatchNum) error {
 		}
 		s.MT = mt
 	}
-	log.Debugw("Making StateDB Reset", "batch", batchNum)
 	return nil
 }

@@ -478,13 +477,13 @@ func NewLocalStateDB(path string, keep int, synchronizerDB *StateDB, typ TypeSta
 // If fromSynchronizer is false, get the state from LocalStateDB checkpoints.
 func (l *LocalStateDB) Reset(batchNum common.BatchNum, fromSynchronizer bool) error {
 	if fromSynchronizer {
-		err := l.db.ResetFromSynchronizer(batchNum, l.synchronizerStateDB.db)
-		if err != nil {
+		if err := l.db.ResetFromSynchronizer(batchNum, l.synchronizerStateDB.db); err != nil {
 			return tracerr.Wrap(err)
 		}
 		// open the MT for the current s.db
 		if l.MT != nil {
-			mt, err := merkletree.NewMerkleTree(l.db.StorageWithPrefix(PrefixKeyMT), l.MT.MaxLevels())
+			mt, err := merkletree.NewMerkleTree(l.db.StorageWithPrefix(PrefixKeyMT),
+				l.MT.MaxLevels())
 			if err != nil {
 				return tracerr.Wrap(err)
 			}
--- a/db/statedb/statedb_test.go
+++ b/db/statedb/statedb_test.go
@@ -116,7 +116,7 @@ func TestNewStateDBIntermediateState(t *testing.T) {
 	bn, err := sdb.getCurrentBatch()
 	require.NoError(t, err)
 	assert.Equal(t, common.BatchNum(0), bn)
-	err = sdb.db.MakeCheckpoint()
+	err = sdb.MakeCheckpoint()
 	require.NoError(t, err)
 	bn, err = sdb.getCurrentBatch()
 	require.NoError(t, err)
@@ -399,14 +399,12 @@ func TestCheckpoints(t *testing.T) {
 	err = ldb2.Reset(4, true)
 	require.NoError(t, err)
 	// check that currentBatch is 4 after the Reset
-	cb, err = ldb2.db.GetCurrentBatch()
-	require.NoError(t, err)
+	cb = ldb2.CurrentBatch()
 	assert.Equal(t, common.BatchNum(4), cb)
 	// advance one checkpoint in ldb2
-	err = ldb2.db.MakeCheckpoint()
-	require.NoError(t, err)
-	cb, err = ldb2.db.GetCurrentBatch()
+	err = ldb2.MakeCheckpoint()
 	require.NoError(t, err)
+	cb = ldb2.CurrentBatch()
 	assert.Equal(t, common.BatchNum(5), cb)

 	debug := false
@@ -624,3 +622,24 @@ func TestCurrentIdx(t *testing.T) {
 	idx = sdb.CurrentIdx()
 	assert.Equal(t, common.Idx(255), idx)
 }
+
+func TestResetFromBadCheckpoint(t *testing.T) {
+	dir, err := ioutil.TempDir("", "tmpdb")
+	require.NoError(t, err)
+	defer require.NoError(t, os.RemoveAll(dir))
+
+	keep := 16
+	sdb, err := NewStateDB(dir, keep, TypeSynchronizer, 32)
+	require.NoError(t, err)
+
+	err = sdb.MakeCheckpoint()
+	require.NoError(t, err)
+	err = sdb.MakeCheckpoint()
+	require.NoError(t, err)
+	err = sdb.MakeCheckpoint()
+	require.NoError(t, err)
+
+	// reset from a checkpoint that doesn't exist
+	err = sdb.Reset(10)
+	require.Error(t, err)
+}
--- a/eth/auction.go
+++ b/eth/auction.go
@@ -254,7 +254,7 @@ type AuctionInterface interface {
 	//

 	AuctionConstants() (*common.AuctionConstants, error)
-	AuctionEventsByBlock(blockNum int64) (*AuctionEvents, *ethCommon.Hash, error)
+	AuctionEventsByBlock(blockNum int64, blockHash *ethCommon.Hash) (*AuctionEvents, error)
 	AuctionEventInit() (*AuctionEventInitialize, int64, error)
 }

@@ -797,15 +797,22 @@ func (c *AuctionClient) AuctionEventInit() (*AuctionEventInitialize, int64, erro
 }

 // AuctionEventsByBlock returns the events in a block that happened in the
-// Auction Smart Contract and the blockHash where the eents happened.  If there
-// are no events in that block, blockHash is nil.
-func (c *AuctionClient) AuctionEventsByBlock(blockNum int64) (*AuctionEvents, *ethCommon.Hash, error) {
+// Auction Smart Contract.
+// To query by blockNum, set blockNum >= 0 and blockHash == nil.
+// To query by blockHash, set blockNum == -1 and blockHash != nil.
+// If there are no events in that block the result is nil.
+func (c *AuctionClient) AuctionEventsByBlock(blockNum int64,
+	blockHash *ethCommon.Hash) (*AuctionEvents, error) {
 	var auctionEvents AuctionEvents
-	var blockHash *ethCommon.Hash

+	var blockNumBigInt *big.Int
+	if blockNum >= 0 {
+		blockNumBigInt = big.NewInt(blockNum)
+	}
 	query := ethereum.FilterQuery{
-		FromBlock: big.NewInt(blockNum),
-		ToBlock:   big.NewInt(blockNum),
+		BlockHash: blockHash,
+		FromBlock: blockNumBigInt,
+		ToBlock:   blockNumBigInt,
 		Addresses: []ethCommon.Address{
 			c.address,
 		},
@@ -814,15 +821,16 @@ func (c *AuctionClient) AuctionEventsByBlock(blockNum int64) (*AuctionEvents, *e

 	logs, err := c.client.client.FilterLogs(context.TODO(), query)
 	if err != nil {
-		return nil, nil, tracerr.Wrap(err)
+		return nil, tracerr.Wrap(err)
 	}
-	if len(logs) > 0 {
-		blockHash = &logs[0].BlockHash
+	if len(logs) == 0 {
+		return nil, nil
 	}
+
 	for _, vLog := range logs {
-		if vLog.BlockHash != *blockHash {
+		if blockHash != nil && vLog.BlockHash != *blockHash {
 			log.Errorw("Block hash mismatch", "expected", blockHash.String(), "got", vLog.BlockHash.String())
-			return nil, nil, tracerr.Wrap(ErrBlockHashMismatchEvent)
+			return nil, tracerr.Wrap(ErrBlockHashMismatchEvent)
 		}
 		switch vLog.Topics[0] {
 		case logAuctionNewBid:
@@ -833,7 +841,7 @@ func (c *AuctionClient) AuctionEventsByBlock(blockNum int64) (*AuctionEvents, *e
 			}
 			var newBid AuctionEventNewBid
 			if err := c.contractAbi.UnpackIntoInterface(&auxNewBid, "NewBid", vLog.Data); err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			newBid.BidAmount = auxNewBid.BidAmount
 			newBid.Slot = new(big.Int).SetBytes(vLog.Topics[1][:]).Int64()
@@ -842,19 +850,19 @@ func (c *AuctionClient) AuctionEventsByBlock(blockNum int64) (*AuctionEvents, *e
 		case logAuctionNewSlotDeadline:
 			var newSlotDeadline AuctionEventNewSlotDeadline
 			if err := c.contractAbi.UnpackIntoInterface(&newSlotDeadline, "NewSlotDeadline", vLog.Data); err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			auctionEvents.NewSlotDeadline = append(auctionEvents.NewSlotDeadline, newSlotDeadline)
 		case logAuctionNewClosedAuctionSlots:
 			var newClosedAuctionSlots AuctionEventNewClosedAuctionSlots
 			if err := c.contractAbi.UnpackIntoInterface(&newClosedAuctionSlots, "NewClosedAuctionSlots", vLog.Data); err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			auctionEvents.NewClosedAuctionSlots = append(auctionEvents.NewClosedAuctionSlots, newClosedAuctionSlots)
 		case logAuctionNewOutbidding:
 			var newOutbidding AuctionEventNewOutbidding
 			if err := c.contractAbi.UnpackIntoInterface(&newOutbidding, "NewOutbidding", vLog.Data); err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			auctionEvents.NewOutbidding = append(auctionEvents.NewOutbidding, newOutbidding)
 		case logAuctionNewDonationAddress:
@@ -864,26 +872,26 @@ func (c *AuctionClient) AuctionEventsByBlock(blockNum int64) (*AuctionEvents, *e
 		case logAuctionNewBootCoordinator:
 			var newBootCoordinator AuctionEventNewBootCoordinator
 			if err := c.contractAbi.UnpackIntoInterface(&newBootCoordinator, "NewBootCoordinator", vLog.Data); err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			newBootCoordinator.NewBootCoordinator = ethCommon.BytesToAddress(vLog.Topics[1].Bytes())
 			auctionEvents.NewBootCoordinator = append(auctionEvents.NewBootCoordinator, newBootCoordinator)
 		case logAuctionNewOpenAuctionSlots:
 			var newOpenAuctionSlots AuctionEventNewOpenAuctionSlots
 			if err := c.contractAbi.UnpackIntoInterface(&newOpenAuctionSlots, "NewOpenAuctionSlots", vLog.Data); err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			auctionEvents.NewOpenAuctionSlots = append(auctionEvents.NewOpenAuctionSlots, newOpenAuctionSlots)
 		case logAuctionNewAllocationRatio:
 			var newAllocationRatio AuctionEventNewAllocationRatio
 			if err := c.contractAbi.UnpackIntoInterface(&newAllocationRatio, "NewAllocationRatio", vLog.Data); err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			auctionEvents.NewAllocationRatio = append(auctionEvents.NewAllocationRatio, newAllocationRatio)
 		case logAuctionSetCoordinator:
 			var setCoordinator AuctionEventSetCoordinator
 			if err := c.contractAbi.UnpackIntoInterface(&setCoordinator, "SetCoordinator", vLog.Data); err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			setCoordinator.BidderAddress = ethCommon.BytesToAddress(vLog.Topics[1].Bytes())
 			setCoordinator.ForgerAddress = ethCommon.BytesToAddress(vLog.Topics[2].Bytes())
@@ -891,7 +899,7 @@ func (c *AuctionClient) AuctionEventsByBlock(blockNum int64) (*AuctionEvents, *e
 		case logAuctionNewForgeAllocated:
 			var newForgeAllocated AuctionEventNewForgeAllocated
 			if err := c.contractAbi.UnpackIntoInterface(&newForgeAllocated, "NewForgeAllocated", vLog.Data); err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			newForgeAllocated.Bidder = ethCommon.BytesToAddress(vLog.Topics[1].Bytes())
 			newForgeAllocated.Forger = ethCommon.BytesToAddress(vLog.Topics[2].Bytes())
@@ -904,7 +912,7 @@ func (c *AuctionClient) AuctionEventsByBlock(blockNum int64) (*AuctionEvents, *e
 			}
 			var newDefaultSlotSetBid AuctionEventNewDefaultSlotSetBid
 			if err := c.contractAbi.UnpackIntoInterface(&auxNewDefaultSlotSetBid, "NewDefaultSlotSetBid", vLog.Data); err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			newDefaultSlotSetBid.NewInitialMinBid = auxNewDefaultSlotSetBid.NewInitialMinBid
 			newDefaultSlotSetBid.SlotSet = auxNewDefaultSlotSetBid.SlotSet.Int64()
@@ -917,11 +925,11 @@ func (c *AuctionClient) AuctionEventsByBlock(blockNum int64) (*AuctionEvents, *e
 		case logAuctionHEZClaimed:
 			var HEZClaimed AuctionEventHEZClaimed
 			if err := c.contractAbi.UnpackIntoInterface(&HEZClaimed, "HEZClaimed", vLog.Data); err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			HEZClaimed.Owner = ethCommon.BytesToAddress(vLog.Topics[1].Bytes())
 			auctionEvents.HEZClaimed = append(auctionEvents.HEZClaimed, HEZClaimed)
 		}
 	}
-	return &auctionEvents, blockHash, nil
+	return &auctionEvents, nil
 }
--- a/eth/auction_test.go
+++ b/eth/auction_test.go
@@ -88,7 +88,7 @@ func TestAuctionSetSlotDeadline(t *testing.T) {
 	assert.Equal(t, newSlotDeadline, slotDeadline)
 	currentBlockNum, err := auctionClientTest.client.EthLastBlock()
 	require.Nil(t, err)
-	auctionEvents, _, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum)
+	auctionEvents, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum, nil)
 	require.Nil(t, err)
 	assert.Equal(t, newSlotDeadline, auctionEvents.NewSlotDeadline[0].NewSlotDeadline)
 }
@@ -109,7 +109,7 @@ func TestAuctionSetOpenAuctionSlots(t *testing.T) {
 	assert.Equal(t, newOpenAuctionSlots, openAuctionSlots)
 	currentBlockNum, err := auctionClientTest.client.EthLastBlock()
 	require.Nil(t, err)
-	auctionEvents, _, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum)
+	auctionEvents, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum, nil)
 	require.Nil(t, err)
 	assert.Equal(t, newOpenAuctionSlots, auctionEvents.NewOpenAuctionSlots[0].NewOpenAuctionSlots)
 }
@@ -130,7 +130,7 @@ func TestAuctionSetClosedAuctionSlots(t *testing.T) {
 	assert.Equal(t, newClosedAuctionSlots, closedAuctionSlots)
 	currentBlockNum, err := auctionClientTest.client.EthLastBlock()
 	require.Nil(t, err)
-	auctionEvents, _, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum)
+	auctionEvents, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum, nil)
 	require.Nil(t, err)
 	assert.Equal(t, newClosedAuctionSlots, auctionEvents.NewClosedAuctionSlots[0].NewClosedAuctionSlots)
 	_, err = auctionClientTest.AuctionSetClosedAuctionSlots(closedAuctionSlots)
@@ -153,7 +153,7 @@ func TestAuctionSetOutbidding(t *testing.T) {
 	assert.Equal(t, newOutbidding, outbidding)
 	currentBlockNum, err := auctionClientTest.client.EthLastBlock()
 	require.Nil(t, err)
-	auctionEvents, _, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum)
+	auctionEvents, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum, nil)
 	require.Nil(t, err)
 	assert.Equal(t, newOutbidding, auctionEvents.NewOutbidding[0].NewOutbidding)
 	_, err = auctionClientTest.AuctionSetOutbidding(outbiddingConst)
@@ -176,7 +176,7 @@ func TestAuctionSetAllocationRatio(t *testing.T) {
 	assert.Equal(t, newAllocationRatio, allocationRatio)
 	currentBlockNum, err := auctionClientTest.client.EthLastBlock()
 	require.Nil(t, err)
-	auctionEvents, _, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum)
+	auctionEvents, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum, nil)
 	require.Nil(t, err)
 	assert.Equal(t, newAllocationRatio, auctionEvents.NewAllocationRatio[0].NewAllocationRatio)
 	_, err = auctionClientTest.AuctionSetAllocationRatio(allocationRatioConst)
@@ -205,7 +205,7 @@ func TestAuctionSetDonationAddress(t *testing.T) {
 	assert.Equal(t, &newDonationAddress, donationAddress)
 	currentBlockNum, err := auctionClientTest.client.EthLastBlock()
 	require.Nil(t, err)
-	auctionEvents, _, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum)
+	auctionEvents, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum, nil)
 	require.Nil(t, err)
 	assert.Equal(t, newDonationAddress, auctionEvents.NewDonationAddress[0].NewDonationAddress)
 	_, err = auctionClientTest.AuctionSetDonationAddress(donationAddressConst)
@@ -224,7 +224,7 @@ func TestAuctionSetBootCoordinator(t *testing.T) {
 	assert.Equal(t, &newBootCoordinator, bootCoordinator)
 	currentBlockNum, err := auctionClientTest.client.EthLastBlock()
 	require.Nil(t, err)
-	auctionEvents, _, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum)
+	auctionEvents, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum, nil)
 	require.Nil(t, err)
 	assert.Equal(t, newBootCoordinator, auctionEvents.NewBootCoordinator[0].NewBootCoordinator)
 	assert.Equal(t, newBootCoordinatorURL, auctionEvents.NewBootCoordinator[0].NewBootCoordinatorURL)
@@ -261,7 +261,7 @@ func TestAuctionChangeDefaultSlotSetBid(t *testing.T) {
 	assert.Equal(t, minBid, newInitialMinBid)
 	currentBlockNum, err := auctionClientTest.client.EthLastBlock()
 	require.Nil(t, err)
-	auctionEvents, _, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum)
+	auctionEvents, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum, nil)
 	require.Nil(t, err)
 	assert.Equal(t, slotSet, auctionEvents.NewDefaultSlotSetBid[0].SlotSet)
 	assert.Equal(t, newInitialMinBid, auctionEvents.NewDefaultSlotSetBid[0].NewInitialMinBid)
@@ -287,7 +287,7 @@ func TestAuctionRegisterCoordinator(t *testing.T) {
 	require.Nil(t, err)
 	currentBlockNum, err := auctionClientTest.client.EthLastBlock()
 	require.Nil(t, err)
-	auctionEvents, _, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum)
+	auctionEvents, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum, nil)
 	require.Nil(t, err)
 	assert.Equal(t, forgerAddress, auctionEvents.SetCoordinator[0].ForgerAddress)
 	assert.Equal(t, bidderAddress, auctionEvents.SetCoordinator[0].BidderAddress)
@@ -306,7 +306,7 @@ func TestAuctionBid(t *testing.T) {
 	require.Nil(t, err)
 	currentBlockNum, err := auctionClientTest.client.EthLastBlock()
 	require.Nil(t, err)
-	auctionEvents, _, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum)
+	auctionEvents, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum, nil)
 	require.Nil(t, err)
 	assert.Equal(t, bidAmount, auctionEvents.NewBid[0].BidAmount)
 	assert.Equal(t, bidderAddress, auctionEvents.NewBid[0].Bidder)
@@ -346,7 +346,7 @@ func TestAuctionMultiBid(t *testing.T) {
 	require.Nil(t, err)
 	currentBlockNum, err := auctionClientTest.client.EthLastBlock()
 	require.Nil(t, err)
-	auctionEvents, _, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum)
+	auctionEvents, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum, nil)
 	require.Nil(t, err)
 	assert.Equal(t, bidderAddress, auctionEvents.NewBid[0].Bidder)
 	assert.Equal(t, currentSlot+4, auctionEvents.NewBid[0].Slot)
@@ -376,7 +376,7 @@ func TestAuctionClaimHEZ(t *testing.T) {
 	require.Nil(t, err)
 	currentBlockNum, err := auctionClientTest.client.EthLastBlock()
 	require.Nil(t, err)
-	auctionEvents, _, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum)
+	auctionEvents, err := auctionClientTest.AuctionEventsByBlock(currentBlockNum, nil)
 	require.Nil(t, err)
 	assert.Equal(t, amount, auctionEvents.HEZClaimed[0].Amount)
 	assert.Equal(t, governanceAddressConst, auctionEvents.HEZClaimed[0].Owner)
--- a/eth/rollup.go
+++ b/eth/rollup.go
@@ -264,7 +264,7 @@ type RollupInterface interface {
 	//

 	RollupConstants() (*common.RollupConstants, error)
-	RollupEventsByBlock(blockNum int64) (*RollupEvents, *ethCommon.Hash, error)
+	RollupEventsByBlock(blockNum int64, blockHash *ethCommon.Hash) (*RollupEvents, error)
 	RollupForgeBatchArgs(ethCommon.Hash, uint16) (*RollupForgeBatchArgs, *ethCommon.Address, error)
 	RollupEventInit() (*RollupEventInitialize, int64, error)
 }
@@ -735,31 +735,40 @@ func (c *RollupClient) RollupEventInit() (*RollupEventInitialize, int64, error)
 	return &rollupInit, int64(vLog.BlockNumber), tracerr.Wrap(err)
 }

-// RollupEventsByBlock returns the events in a block that happened in the Rollup Smart Contract
-func (c *RollupClient) RollupEventsByBlock(blockNum int64) (*RollupEvents, *ethCommon.Hash, error) {
+// RollupEventsByBlock returns the events in a block that happened in the
+// Rollup Smart Contract.
+// To query by blockNum, set blockNum >= 0 and blockHash == nil.
+// To query by blockHash, set blockNum == -1 and blockHash != nil.
+// If there are no events in that block the result is nil.
+func (c *RollupClient) RollupEventsByBlock(blockNum int64,
+	blockHash *ethCommon.Hash) (*RollupEvents, error) {
 	var rollupEvents RollupEvents
-	var blockHash *ethCommon.Hash

+	var blockNumBigInt *big.Int
+	if blockNum >= 0 {
+		blockNumBigInt = big.NewInt(blockNum)
+	}
 	query := ethereum.FilterQuery{
-		FromBlock: big.NewInt(blockNum),
-		ToBlock:   big.NewInt(blockNum),
+		BlockHash: blockHash,
+		FromBlock: blockNumBigInt,
+		ToBlock:   blockNumBigInt,
 		Addresses: []ethCommon.Address{
 			c.address,
 		},
-		BlockHash: nil,
-		Topics:    [][]ethCommon.Hash{},
+		Topics: [][]ethCommon.Hash{},
 	}
 	logs, err := c.client.client.FilterLogs(context.Background(), query)
 	if err != nil {
-		return nil, nil, tracerr.Wrap(err)
+		return nil, tracerr.Wrap(err)
 	}
-	if len(logs) > 0 {
-		blockHash = &logs[0].BlockHash
+	if len(logs) == 0 {
+		return nil, nil
 	}
+
 	for _, vLog := range logs {
-		if vLog.BlockHash != *blockHash {
+		if blockHash != nil && vLog.BlockHash != *blockHash {
 			log.Errorw("Block hash mismatch", "expected", blockHash.String(), "got", vLog.BlockHash.String())
-			return nil, nil, tracerr.Wrap(ErrBlockHashMismatchEvent)
+			return nil, tracerr.Wrap(ErrBlockHashMismatchEvent)
 		}
 		switch vLog.Topics[0] {
 		case logHermezL1UserTxEvent:
@@ -767,11 +776,11 @@ func (c *RollupClient) RollupEventsByBlock(blockNum int64) (*RollupEvents, *ethC
 			var L1UserTx RollupEventL1UserTx
 			err := c.contractAbi.UnpackIntoInterface(&L1UserTxAux, "L1UserTxEvent", vLog.Data)
 			if err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			L1Tx, err := common.L1UserTxFromBytes(L1UserTxAux.L1UserTx)
 			if err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			toForgeL1TxsNum := new(big.Int).SetBytes(vLog.Topics[1][:]).Int64()
 			L1Tx.ToForgeL1TxsNum = &toForgeL1TxsNum
@@ -783,7 +792,7 @@ func (c *RollupClient) RollupEventsByBlock(blockNum int64) (*RollupEvents, *ethC
 			var addToken RollupEventAddToken
 			err := c.contractAbi.UnpackIntoInterface(&addToken, "AddToken", vLog.Data)
 			if err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			addToken.TokenAddress = ethCommon.BytesToAddress(vLog.Topics[1].Bytes())
 			rollupEvents.AddToken = append(rollupEvents.AddToken, addToken)
@@ -791,7 +800,7 @@ func (c *RollupClient) RollupEventsByBlock(blockNum int64) (*RollupEvents, *ethC
 			var forgeBatch RollupEventForgeBatch
 			err := c.contractAbi.UnpackIntoInterface(&forgeBatch, "ForgeBatch", vLog.Data)
 			if err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			forgeBatch.BatchNum = new(big.Int).SetBytes(vLog.Topics[1][:]).Int64()
 			forgeBatch.EthTxHash = vLog.TxHash
@@ -803,7 +812,7 @@ func (c *RollupClient) RollupEventsByBlock(blockNum int64) (*RollupEvents, *ethC
 			}
 			err := c.contractAbi.UnpackIntoInterface(&updateForgeL1L2BatchTimeout, "UpdateForgeL1L2BatchTimeout", vLog.Data)
 			if err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			rollupEvents.UpdateForgeL1L2BatchTimeout = append(rollupEvents.UpdateForgeL1L2BatchTimeout,
 				RollupEventUpdateForgeL1L2BatchTimeout{
@@ -813,7 +822,7 @@ func (c *RollupClient) RollupEventsByBlock(blockNum int64) (*RollupEvents, *ethC
 			var updateFeeAddToken RollupEventUpdateFeeAddToken
 			err := c.contractAbi.UnpackIntoInterface(&updateFeeAddToken, "UpdateFeeAddToken", vLog.Data)
 			if err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			rollupEvents.UpdateFeeAddToken = append(rollupEvents.UpdateFeeAddToken, updateFeeAddToken)
 		case logHermezWithdrawEvent:
@@ -831,7 +840,7 @@ func (c *RollupClient) RollupEventsByBlock(blockNum int64) (*RollupEvents, *ethC
 			var updateBucketWithdraw RollupEventUpdateBucketWithdraw
 			err := c.contractAbi.UnpackIntoInterface(&updateBucketWithdrawAux, "UpdateBucketWithdraw", vLog.Data)
 			if err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			updateBucketWithdraw.Withdrawals = updateBucketWithdrawAux.Withdrawals
 			updateBucketWithdraw.NumBucket = int(new(big.Int).SetBytes(vLog.Topics[1][:]).Int64())
@@ -842,7 +851,7 @@ func (c *RollupClient) RollupEventsByBlock(blockNum int64) (*RollupEvents, *ethC
 			var withdrawalDelay RollupEventUpdateWithdrawalDelay
 			err := c.contractAbi.UnpackIntoInterface(&withdrawalDelay, "UpdateWithdrawalDelay", vLog.Data)
 			if err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			rollupEvents.UpdateWithdrawalDelay = append(rollupEvents.UpdateWithdrawalDelay, withdrawalDelay)
 		case logHermezUpdateBucketsParameters:
@@ -850,7 +859,7 @@ func (c *RollupClient) RollupEventsByBlock(blockNum int64) (*RollupEvents, *ethC
 			var bucketsParameters RollupEventUpdateBucketsParameters
 			err := c.contractAbi.UnpackIntoInterface(&bucketsParametersAux, "UpdateBucketsParameters", vLog.Data)
 			if err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			for i, bucket := range bucketsParametersAux.ArrayBuckets {
 				bucketsParameters.ArrayBuckets[i].CeilUSD = bucket[0]
@@ -863,7 +872,7 @@ func (c *RollupClient) RollupEventsByBlock(blockNum int64) (*RollupEvents, *ethC
 			var tokensExchange RollupEventUpdateTokenExchange
 			err := c.contractAbi.UnpackIntoInterface(&tokensExchange, "UpdateTokenExchange", vLog.Data)
 			if err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			rollupEvents.UpdateTokenExchange = append(rollupEvents.UpdateTokenExchange, tokensExchange)
 		case logHermezSafeMode:
@@ -885,7 +894,7 @@ func (c *RollupClient) RollupEventsByBlock(blockNum int64) (*RollupEvents, *ethC
 				bucketsParameters)
 		}
 	}
-	return &rollupEvents, blockHash, nil
+	return &rollupEvents, nil
 }

 // RollupForgeBatchArgs returns the arguments used in a ForgeBatch call in the
@@ -893,7 +902,7 @@ func (c *RollupClient) RollupEventsByBlock(blockNum int64) (*RollupEvents, *ethC
 func (c *RollupClient) RollupForgeBatchArgs(ethTxHash ethCommon.Hash, l1UserTxsLen uint16) (*RollupForgeBatchArgs, *ethCommon.Address, error) {
 	tx, _, err := c.client.client.TransactionByHash(context.Background(), ethTxHash)
 	if err != nil {
-		return nil, nil, tracerr.Wrap(err)
+		return nil, nil, tracerr.Wrap(fmt.Errorf("TransactionByHash: %w", err))
 	}
 	txData := tx.Data()

--- a/eth/rollup_test.go
+++ b/eth/rollup_test.go
@@ -91,7 +91,7 @@ func TestRollupAddToken(t *testing.T) {
 	require.NoError(t, err)
 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)

 	assert.Equal(t, tokenHEZAddressConst, rollupEvents.AddToken[0].TokenAddress)
@@ -174,7 +174,7 @@ func TestRollupForgeBatch(t *testing.T) {

 	currentBlockNum, err = rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)

 	assert.Equal(t, int64(1), rollupEvents.ForgeBatch[0].BatchNum)
@@ -203,7 +203,7 @@ func TestRollupUpdateForgeL1L2BatchTimeout(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)

 	assert.Equal(t, newForgeL1L2BatchTimeout, rollupEvents.UpdateForgeL1L2BatchTimeout[0].NewForgeL1L2BatchTimeout)
@@ -216,7 +216,7 @@ func TestRollupUpdateFeeAddToken(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)

 	assert.Equal(t, newFeeAddToken, rollupEvents.UpdateFeeAddToken[0].NewFeeAddToken)
@@ -235,7 +235,7 @@ func TestRollupUpdateBucketsParameters(t *testing.T) {
 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
 	blockStampBucket = currentBlockNum
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	assert.Equal(t, bucketsParameters, rollupEvents.UpdateBucketsParameters[0].ArrayBuckets)
 }
@@ -246,7 +246,7 @@ func TestRollupUpdateWithdrawalDelay(t *testing.T) {
 	require.NoError(t, err)
 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	assert.Equal(t, newWithdrawalDelay, int64(rollupEvents.UpdateWithdrawalDelay[0].NewWithdrawalDelay))
 }
@@ -263,7 +263,7 @@ func TestRollupUpdateTokenExchange(t *testing.T) {
 	require.NoError(t, err)
 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	assert.Equal(t, addressArray, rollupEvents.UpdateTokenExchange[0].AddressArray)
 	assert.Equal(t, valueArray, rollupEvents.UpdateTokenExchange[0].ValueArray)
@@ -292,7 +292,7 @@ func TestRollupL1UserTxETHCreateAccountDeposit(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	assert.Equal(t, l1Tx.FromBJJ, rollupEvents.L1UserTx[0].L1UserTx.FromBJJ)
 	assert.Equal(t, l1Tx.ToIdx, rollupEvents.L1UserTx[0].L1UserTx.ToIdx)
@@ -324,7 +324,7 @@ func TestRollupL1UserTxERC20CreateAccountDeposit(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	assert.Equal(t, l1Tx.FromBJJ, rollupEvents.L1UserTx[0].L1UserTx.FromBJJ)
 	assert.Equal(t, l1Tx.ToIdx, rollupEvents.L1UserTx[0].L1UserTx.ToIdx)
@@ -356,7 +356,7 @@ func TestRollupL1UserTxERC20PermitCreateAccountDeposit(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	assert.Equal(t, l1Tx.FromBJJ, rollupEvents.L1UserTx[0].L1UserTx.FromBJJ)
 	assert.Equal(t, l1Tx.ToIdx, rollupEvents.L1UserTx[0].L1UserTx.ToIdx)
@@ -388,7 +388,7 @@ func TestRollupL1UserTxETHDeposit(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	assert.Equal(t, l1Tx.ToIdx, rollupEvents.L1UserTx[0].L1UserTx.ToIdx)
 	assert.Equal(t, l1Tx.DepositAmount, rollupEvents.L1UserTx[0].L1UserTx.DepositAmount)
@@ -418,7 +418,7 @@ func TestRollupL1UserTxERC20Deposit(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	assert.Equal(t, l1Tx.ToIdx, rollupEvents.L1UserTx[0].L1UserTx.ToIdx)
 	assert.Equal(t, l1Tx.DepositAmount, rollupEvents.L1UserTx[0].L1UserTx.DepositAmount)
@@ -447,7 +447,7 @@ func TestRollupL1UserTxERC20PermitDeposit(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	assert.Equal(t, l1Tx.ToIdx, rollupEvents.L1UserTx[0].L1UserTx.ToIdx)
 	assert.Equal(t, l1Tx.DepositAmount, rollupEvents.L1UserTx[0].L1UserTx.DepositAmount)
@@ -478,7 +478,7 @@ func TestRollupL1UserTxETHDepositTransfer(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	assert.Equal(t, l1Tx.ToIdx, rollupEvents.L1UserTx[0].L1UserTx.ToIdx)
 	assert.Equal(t, l1Tx.DepositAmount, rollupEvents.L1UserTx[0].L1UserTx.DepositAmount)
@@ -508,7 +508,7 @@ func TestRollupL1UserTxERC20DepositTransfer(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	assert.Equal(t, l1Tx.ToIdx, rollupEvents.L1UserTx[0].L1UserTx.ToIdx)
 	assert.Equal(t, l1Tx.DepositAmount, rollupEvents.L1UserTx[0].L1UserTx.DepositAmount)
@@ -538,7 +538,7 @@ func TestRollupL1UserTxERC20PermitDepositTransfer(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	assert.Equal(t, l1Tx.ToIdx, rollupEvents.L1UserTx[0].L1UserTx.ToIdx)
 	assert.Equal(t, l1Tx.DepositAmount, rollupEvents.L1UserTx[0].L1UserTx.DepositAmount)
@@ -569,7 +569,7 @@ func TestRollupL1UserTxETHCreateAccountDepositTransfer(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	assert.Equal(t, l1Tx.ToIdx, rollupEvents.L1UserTx[0].L1UserTx.ToIdx)
 	assert.Equal(t, l1Tx.DepositAmount, rollupEvents.L1UserTx[0].L1UserTx.DepositAmount)
@@ -599,7 +599,7 @@ func TestRollupL1UserTxERC20CreateAccountDepositTransfer(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	assert.Equal(t, l1Tx.ToIdx, rollupEvents.L1UserTx[0].L1UserTx.ToIdx)
 	assert.Equal(t, l1Tx.DepositAmount, rollupEvents.L1UserTx[0].L1UserTx.DepositAmount)
@@ -629,7 +629,7 @@ func TestRollupL1UserTxERC20PermitCreateAccountDepositTransfer(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	assert.Equal(t, l1Tx.ToIdx, rollupEvents.L1UserTx[0].L1UserTx.ToIdx)
 	assert.Equal(t, l1Tx.DepositAmount, rollupEvents.L1UserTx[0].L1UserTx.DepositAmount)
@@ -659,7 +659,7 @@ func TestRollupL1UserTxETHForceTransfer(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	assert.Equal(t, l1Tx.ToIdx, rollupEvents.L1UserTx[0].L1UserTx.ToIdx)
 	assert.Equal(t, l1Tx.DepositAmount, rollupEvents.L1UserTx[0].L1UserTx.DepositAmount)
@@ -688,7 +688,7 @@ func TestRollupL1UserTxERC20ForceTransfer(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	assert.Equal(t, l1Tx.ToIdx, rollupEvents.L1UserTx[0].L1UserTx.ToIdx)
 	assert.Equal(t, l1Tx.DepositAmount, rollupEvents.L1UserTx[0].L1UserTx.DepositAmount)
@@ -717,7 +717,7 @@ func TestRollupL1UserTxERC20PermitForceTransfer(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	assert.Equal(t, l1Tx.ToIdx, rollupEvents.L1UserTx[0].L1UserTx.ToIdx)
 	assert.Equal(t, l1Tx.DepositAmount, rollupEvents.L1UserTx[0].L1UserTx.DepositAmount)
@@ -747,7 +747,7 @@ func TestRollupL1UserTxETHForceExit(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	assert.Equal(t, l1Tx.ToIdx, rollupEvents.L1UserTx[0].L1UserTx.ToIdx)
 	assert.Equal(t, l1Tx.DepositAmount, rollupEvents.L1UserTx[0].L1UserTx.DepositAmount)
@@ -776,7 +776,7 @@ func TestRollupL1UserTxERC20ForceExit(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	assert.Equal(t, l1Tx.ToIdx, rollupEvents.L1UserTx[0].L1UserTx.ToIdx)
 	assert.Equal(t, l1Tx.DepositAmount, rollupEvents.L1UserTx[0].L1UserTx.DepositAmount)
@@ -807,7 +807,7 @@ func TestRollupL1UserTxERC20PermitForceExit(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	assert.Equal(t, l1Tx.ToIdx, rollupEvents.L1UserTx[0].L1UserTx.ToIdx)
 	assert.Equal(t, l1Tx.DepositAmount, rollupEvents.L1UserTx[0].L1UserTx.DepositAmount)
@@ -822,7 +822,7 @@ func TestRollupForgeBatch2(t *testing.T) {
 	require.NoError(t, err)
 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)

 	assert.Equal(t, int64(2), rollupEvents.ForgeBatch[0].BatchNum)
@@ -876,7 +876,7 @@ func TestRollupForgeBatch2(t *testing.T) {

 	currentBlockNum, err = rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err = rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err = rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)

 	assert.Equal(t, int64(3), rollupEvents.ForgeBatch[0].BatchNum)
@@ -928,7 +928,7 @@ func TestRollupWithdrawMerkleProof(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)

 	assert.Equal(t, uint64(fromIdx), rollupEvents.Withdraw[0].Idx)
@@ -951,7 +951,7 @@ func TestRollupSafeMode(t *testing.T) {

 	currentBlockNum, err := rollupClient.client.EthLastBlock()
 	require.NoError(t, err)
-	rollupEvents, _, err := rollupClient.RollupEventsByBlock(currentBlockNum)
+	rollupEvents, err := rollupClient.RollupEventsByBlock(currentBlockNum, nil)
 	require.NoError(t, err)
 	auxEvent := new(RollupEventSafeMode)
 	assert.Equal(t, auxEvent, &rollupEvents.SafeMode[0])
--- a/eth/wdelayer.go
+++ b/eth/wdelayer.go
@@ -134,7 +134,7 @@ type WDelayerInterface interface {
 	WDelayerWithdrawal(owner, token ethCommon.Address) (*types.Transaction, error)
 	WDelayerEscapeHatchWithdrawal(to, token ethCommon.Address, amount *big.Int) (*types.Transaction, error)

-	WDelayerEventsByBlock(blockNum int64) (*WDelayerEvents, *ethCommon.Hash, error)
+	WDelayerEventsByBlock(blockNum int64, blockHash *ethCommon.Hash) (*WDelayerEvents, error)
 	WDelayerConstants() (*common.WDelayerConstants, error)
 	WDelayerEventInit() (*WDelayerEventInitialize, int64, error)
 }
@@ -424,40 +424,47 @@ func (c *WDelayerClient) WDelayerEventInit() (*WDelayerEventInitialize, int64, e
 }

 // WDelayerEventsByBlock returns the events in a block that happened in the
-// WDelayer Smart Contract and the blockHash where the eents happened.  If
-// there are no events in that block, blockHash is nil.
-func (c *WDelayerClient) WDelayerEventsByBlock(blockNum int64) (*WDelayerEvents, *ethCommon.Hash, error) {
+// WDelayer Smart Contract.
+// To query by blockNum, set blockNum >= 0 and blockHash == nil.
+// To query by blockHash, set blockNum == -1 and blockHash != nil.
+// If there are no events in that block the result is nil.
+func (c *WDelayerClient) WDelayerEventsByBlock(blockNum int64,
+	blockHash *ethCommon.Hash) (*WDelayerEvents, error) {
 	var wdelayerEvents WDelayerEvents
-	var blockHash *ethCommon.Hash

+	var blockNumBigInt *big.Int
+	if blockNum >= 0 {
+		blockNumBigInt = big.NewInt(blockNum)
+	}
 	query := ethereum.FilterQuery{
-		FromBlock: big.NewInt(blockNum),
-		ToBlock:   big.NewInt(blockNum),
+		BlockHash: blockHash,
+		FromBlock: blockNumBigInt,
+		ToBlock:   blockNumBigInt,
 		Addresses: []ethCommon.Address{
 			c.address,
 		},
-		BlockHash: nil,
-		Topics:    [][]ethCommon.Hash{},
+		Topics: [][]ethCommon.Hash{},
 	}

 	logs, err := c.client.client.FilterLogs(context.Background(), query)
 	if err != nil {
-		return nil, nil, tracerr.Wrap(err)
+		return nil, tracerr.Wrap(err)
 	}
-	if len(logs) > 0 {
-		blockHash = &logs[0].BlockHash
+	if len(logs) == 0 {
+		return nil, nil
 	}
+
 	for _, vLog := range logs {
-		if vLog.BlockHash != *blockHash {
+		if blockHash != nil && vLog.BlockHash != *blockHash {
 			log.Errorw("Block hash mismatch", "expected", blockHash.String(), "got", vLog.BlockHash.String())
-			return nil, nil, tracerr.Wrap(ErrBlockHashMismatchEvent)
+			return nil, tracerr.Wrap(ErrBlockHashMismatchEvent)
 		}
 		switch vLog.Topics[0] {
 		case logWDelayerDeposit:
 			var deposit WDelayerEventDeposit
 			err := c.contractAbi.UnpackIntoInterface(&deposit, "Deposit", vLog.Data)
 			if err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			deposit.Owner = ethCommon.BytesToAddress(vLog.Topics[1].Bytes())
 			deposit.Token = ethCommon.BytesToAddress(vLog.Topics[2].Bytes())
@@ -468,7 +475,7 @@ func (c *WDelayerClient) WDelayerEventsByBlock(blockNum int64) (*WDelayerEvents,
 			var withdraw WDelayerEventWithdraw
 			err := c.contractAbi.UnpackIntoInterface(&withdraw, "Withdraw", vLog.Data)
 			if err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			withdraw.Token = ethCommon.BytesToAddress(vLog.Topics[1].Bytes())
 			withdraw.Owner = ethCommon.BytesToAddress(vLog.Topics[2].Bytes())
@@ -482,7 +489,7 @@ func (c *WDelayerClient) WDelayerEventsByBlock(blockNum int64) (*WDelayerEvents,
 			var withdrawalDelay WDelayerEventNewWithdrawalDelay
 			err := c.contractAbi.UnpackIntoInterface(&withdrawalDelay, "NewWithdrawalDelay", vLog.Data)
 			if err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			wdelayerEvents.NewWithdrawalDelay = append(wdelayerEvents.NewWithdrawalDelay, withdrawalDelay)

@@ -490,7 +497,7 @@ func (c *WDelayerClient) WDelayerEventsByBlock(blockNum int64) (*WDelayerEvents,
 			var escapeHatchWithdrawal WDelayerEventEscapeHatchWithdrawal
 			err := c.contractAbi.UnpackIntoInterface(&escapeHatchWithdrawal, "EscapeHatchWithdrawal", vLog.Data)
 			if err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			escapeHatchWithdrawal.Who = ethCommon.BytesToAddress(vLog.Topics[1].Bytes())
 			escapeHatchWithdrawal.To = ethCommon.BytesToAddress(vLog.Topics[2].Bytes())
@@ -501,7 +508,7 @@ func (c *WDelayerClient) WDelayerEventsByBlock(blockNum int64) (*WDelayerEvents,
 			var emergencyCouncil WDelayerEventNewEmergencyCouncil
 			err := c.contractAbi.UnpackIntoInterface(&emergencyCouncil, "NewEmergencyCouncil", vLog.Data)
 			if err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			wdelayerEvents.NewEmergencyCouncil = append(wdelayerEvents.NewEmergencyCouncil, emergencyCouncil)

@@ -509,10 +516,10 @@ func (c *WDelayerClient) WDelayerEventsByBlock(blockNum int64) (*WDelayerEvents,
 			var governanceAddress WDelayerEventNewHermezGovernanceAddress
 			err := c.contractAbi.UnpackIntoInterface(&governanceAddress, "NewHermezGovernanceAddress", vLog.Data)
 			if err != nil {
-				return nil, nil, tracerr.Wrap(err)
+				return nil, tracerr.Wrap(err)
 			}
 			wdelayerEvents.NewHermezGovernanceAddress = append(wdelayerEvents.NewHermezGovernanceAddress, governanceAddress)
 		}
 	}
-	return &wdelayerEvents, blockHash, nil
+	return &wdelayerEvents, nil
 }
--- a/eth/wdelayer_test.go
+++ b/eth/wdelayer_test.go
@@ -52,7 +52,7 @@ func TestWDelayerSetHermezGovernanceAddress(t *testing.T) {
 	assert.Equal(t, &auxAddressConst, auxAddress)
 	currentBlockNum, err := wdelayerClientTest.client.EthLastBlock()
 	require.Nil(t, err)
-	wdelayerEvents, _, err := wdelayerClientTest.WDelayerEventsByBlock(currentBlockNum)
+	wdelayerEvents, err := wdelayerClientTest.WDelayerEventsByBlock(currentBlockNum, nil)
 	require.Nil(t, err)
 	assert.Equal(t, auxAddressConst, wdelayerEvents.NewHermezGovernanceAddress[0].NewHermezGovernanceAddress)
 	_, err = wdelayerClientAux.WDelayerTransferGovernance(governanceAddressConst)
@@ -81,7 +81,7 @@ func TestWDelayerSetEmergencyCouncil(t *testing.T) {
 	assert.Equal(t, &auxAddressConst, auxAddress)
 	currentBlockNum, err := wdelayerClientTest.client.EthLastBlock()
 	require.Nil(t, err)
-	wdelayerEvents, _, err := wdelayerClientTest.WDelayerEventsByBlock(currentBlockNum)
+	wdelayerEvents, err := wdelayerClientTest.WDelayerEventsByBlock(currentBlockNum, nil)
 	require.Nil(t, err)
 	assert.Equal(t, auxAddressConst, wdelayerEvents.NewEmergencyCouncil[0].NewEmergencyCouncil)
 	_, err = wdelayerClientAux.WDelayerTransferEmergencyCouncil(emergencyCouncilAddressConst)
@@ -110,7 +110,7 @@ func TestWDelayerChangeWithdrawalDelay(t *testing.T) {
 	assert.Equal(t, newWithdrawalDelay, withdrawalDelay)
 	currentBlockNum, err := wdelayerClientTest.client.EthLastBlock()
 	require.Nil(t, err)
-	wdelayerEvents, _, err := wdelayerClientTest.WDelayerEventsByBlock(currentBlockNum)
+	wdelayerEvents, err := wdelayerClientTest.WDelayerEventsByBlock(currentBlockNum, nil)
 	require.Nil(t, err)
 	assert.Equal(t, uint64(newWithdrawalDelay), wdelayerEvents.NewWithdrawalDelay[0].WithdrawalDelay)
 }
@@ -124,7 +124,7 @@ func TestWDelayerDeposit(t *testing.T) {
 	require.Nil(t, err)
 	currentBlockNum, err := wdelayerClientTest.client.EthLastBlock()
 	require.Nil(t, err)
-	wdelayerEvents, _, err := wdelayerClientTest.WDelayerEventsByBlock(currentBlockNum)
+	wdelayerEvents, err := wdelayerClientTest.WDelayerEventsByBlock(currentBlockNum, nil)
 	require.Nil(t, err)
 	assert.Equal(t, amount, wdelayerEvents.Deposit[0].Amount)
 	assert.Equal(t, auxAddressConst, wdelayerEvents.Deposit[0].Owner)
@@ -150,7 +150,7 @@ func TestWDelayerWithdrawal(t *testing.T) {
 	require.Nil(t, err)
 	currentBlockNum, err := wdelayerClientTest.client.EthLastBlock()
 	require.Nil(t, err)
-	wdelayerEvents, _, err := wdelayerClientTest.WDelayerEventsByBlock(currentBlockNum)
+	wdelayerEvents, err := wdelayerClientTest.WDelayerEventsByBlock(currentBlockNum, nil)
 	require.Nil(t, err)
 	assert.Equal(t, amount, wdelayerEvents.Withdraw[0].Amount)
 	assert.Equal(t, auxAddressConst, wdelayerEvents.Withdraw[0].Owner)
@@ -166,7 +166,7 @@ func TestWDelayerSecondDeposit(t *testing.T) {
 	require.Nil(t, err)
 	currentBlockNum, err := wdelayerClientTest.client.EthLastBlock()
 	require.Nil(t, err)
-	wdelayerEvents, _, err := wdelayerClientTest.WDelayerEventsByBlock(currentBlockNum)
+	wdelayerEvents, err := wdelayerClientTest.WDelayerEventsByBlock(currentBlockNum, nil)
 	require.Nil(t, err)
 	assert.Equal(t, amount, wdelayerEvents.Deposit[0].Amount)
 	assert.Equal(t, auxAddressConst, wdelayerEvents.Deposit[0].Owner)
@@ -181,7 +181,7 @@ func TestWDelayerEnableEmergencyMode(t *testing.T) {
 	assert.Equal(t, true, emergencyMode)
 	currentBlockNum, err := wdelayerClientTest.client.EthLastBlock()
 	require.Nil(t, err)
-	wdelayerEvents, _, err := wdelayerClientTest.WDelayerEventsByBlock(currentBlockNum)
+	wdelayerEvents, err := wdelayerClientTest.WDelayerEventsByBlock(currentBlockNum, nil)
 	require.Nil(t, err)
 	auxEvent := new(WDelayerEventEmergencyModeEnabled)
 	assert.Equal(t, auxEvent, &wdelayerEvents.EmergencyModeEnabled[0])
@@ -210,7 +210,7 @@ func TestWDelayerEscapeHatchWithdrawal(t *testing.T) {
 	require.Nil(t, err)
 	currentBlockNum, err := wdelayerClientTest.client.EthLastBlock()
 	require.Nil(t, err)
-	wdelayerEvents, _, err := wdelayerClientTest.WDelayerEventsByBlock(currentBlockNum)
+	wdelayerEvents, err := wdelayerClientTest.WDelayerEventsByBlock(currentBlockNum, nil)
 	require.Nil(t, err)
 	assert.Equal(t, tokenHEZAddressConst, wdelayerEvents.EscapeHatchWithdrawal[0].Token)
 	assert.Equal(t, governanceAddressConst, wdelayerEvents.EscapeHatchWithdrawal[0].To)
--- a/synchronizer/synchronizer.go
+++ b/synchronizer/synchronizer.go
@@ -195,15 +195,16 @@ type Config struct {

 // Synchronizer implements the Synchronizer type
 type Synchronizer struct {
-	ethClient     eth.ClientInterface
-	consts        SCConsts
-	historyDB     *historydb.HistoryDB
-	stateDB       *statedb.StateDB
-	cfg           Config
-	initVars      SCVariables
-	startBlockNum int64
-	vars          SCVariables
-	stats         *StatsHolder
+	ethClient        eth.ClientInterface
+	consts           SCConsts
+	historyDB        *historydb.HistoryDB
+	stateDB          *statedb.StateDB
+	cfg              Config
+	initVars         SCVariables
+	startBlockNum    int64
+	vars             SCVariables
+	stats            *StatsHolder
+	resetStateFailed bool
 }

 // NewSynchronizer creates a new Synchronizer
@@ -445,8 +446,10 @@ func (s *Synchronizer) init() error {
 		lastBlock = lastSavedBlock
 	}
 	if err := s.resetState(lastBlock); err != nil {
+		s.resetStateFailed = true
 		return tracerr.Wrap(err)
 	}
+	s.resetStateFailed = false

 	log.Infow("Sync init block",
 		"syncLastBlock", s.stats.Sync.LastBlock,
@@ -462,16 +465,37 @@ func (s *Synchronizer) init() error {
 	return nil
 }

+func (s *Synchronizer) resetIntermediateState() error {
+	lastBlock, err := s.historyDB.GetLastBlock()
+	if tracerr.Unwrap(err) == sql.ErrNoRows {
+		lastBlock = &common.Block{}
+	} else if err != nil {
+		return tracerr.Wrap(fmt.Errorf("historyDB.GetLastBlock: %w", err))
+	}
+	if err := s.resetState(lastBlock); err != nil {
+		s.resetStateFailed = true
+		return tracerr.Wrap(fmt.Errorf("resetState at block %v: %w", lastBlock.Num, err))
+	}
+	s.resetStateFailed = false
+	return nil
+}
+
 // Sync2 attems to synchronize an ethereum block starting from lastSavedBlock.
 // If lastSavedBlock is nil, the lastSavedBlock value is obtained from de DB.
 // If a block is synched, it will be returned and also stored in the DB.  If a
 // reorg is detected, the number of discarded blocks will be returned and no
 // synchronization will be made.
 // TODO: Be smart about locking: only lock during the read/write operations
-func (s *Synchronizer) Sync2(ctx context.Context, lastSavedBlock *common.Block) (*common.BlockData, *int64, error) {
+func (s *Synchronizer) Sync2(ctx context.Context,
+	lastSavedBlock *common.Block) (blockData *common.BlockData, discarded *int64, err error) {
+	if s.resetStateFailed {
+		if err := s.resetIntermediateState(); err != nil {
+			return nil, nil, tracerr.Wrap(err)
+		}
+	}
+
 	var nextBlockNum int64 // next block number to sync
 	if lastSavedBlock == nil {
-		var err error
 		// Get lastSavedBlock from History DB
 		lastSavedBlock, err = s.historyDB.GetLastBlock()
 		if err != nil && tracerr.Unwrap(err) != sql.ErrNoRows {
@@ -527,6 +551,20 @@ func (s *Synchronizer) Sync2(ctx context.Context, lastSavedBlock *common.Block)
 		}
 	}

+	defer func() {
+		// If there was an error during sync, reset to the last block
+		// in the historyDB because the historyDB is written last in
+		// the Sync method and is the source of consistency.  This
+		// allows reseting the stateDB in the case a batch was
+		// processed but the historyDB block was not committed due to an
+		// error.
+		if err != nil {
+			if err2 := s.resetIntermediateState(); err2 != nil {
+				log.Errorw("sync revert", "err", err2)
+			}
+		}
+	}()
+
 	// Get data from the rollup contract
 	rollupData, err := s.rollupSync(ethBlock)
 	if err != nil {
@@ -564,14 +602,14 @@ func (s *Synchronizer) Sync2(ctx context.Context, lastSavedBlock *common.Block)
 	}

 	// Group all the block data into the structs to save into HistoryDB
-	blockData := common.BlockData{
+	blockData = &common.BlockData{
 		Block:    *ethBlock,
 		Rollup:   *rollupData,
 		Auction:  *auctionData,
 		WDelayer: *wDelayerData,
 	}

-	err = s.historyDB.AddBlockSCData(&blockData)
+	err = s.historyDB.AddBlockSCData(blockData)
 	if err != nil {
 		return nil, nil, tracerr.Wrap(err)
 	}
@@ -613,7 +651,7 @@ func (s *Synchronizer) Sync2(ctx context.Context, lastSavedBlock *common.Block)
 		)
 	}

-	return &blockData, nil, nil
+	return blockData, nil, nil
 }

 // reorg manages a reorg, updating History and State DB as needed.  Keeps
@@ -645,14 +683,15 @@ func (s *Synchronizer) reorg(uncleBlock *common.Block) (int64, error) {
 	log.Debugw("Discarding blocks", "total", total, "from", uncleBlock.Num, "to", block.Num+1)

 	// Set History DB and State DB to the correct state
-	err := s.historyDB.Reorg(block.Num)
-	if err != nil {
+	if err := s.historyDB.Reorg(block.Num); err != nil {
 		return 0, tracerr.Wrap(err)
 	}

 	if err := s.resetState(block); err != nil {
+		s.resetStateFailed = true
 		return 0, tracerr.Wrap(err)
 	}
+	s.resetStateFailed = false

 	return block.Num, nil
 }
@@ -722,6 +761,11 @@ func (s *Synchronizer) resetState(block *common.Block) error {
 		batchNum = 0
 	}

+	err = s.stateDB.Reset(batchNum)
+	if err != nil {
+		return tracerr.Wrap(fmt.Errorf("stateDB.Reset: %w", err))
+	}
+
 	lastL1BatchBlockNum, err := s.historyDB.GetLastL1BatchBlockNum()
 	if err != nil && tracerr.Unwrap(err) != sql.ErrNoRows {
 		return tracerr.Wrap(fmt.Errorf("historyDB.GetLastL1BatchBlockNum: %w", err))
@@ -739,11 +783,6 @@ func (s *Synchronizer) resetState(block *common.Block) error {
 		lastForgeL1TxsNum = &n
 	}

-	err = s.stateDB.Reset(batchNum)
-	if err != nil {
-		return tracerr.Wrap(fmt.Errorf("stateDB.Reset: %w", err))
-	}
-
 	s.stats.UpdateSync(block, &batchNum, &lastL1BatchBlockNum, lastForgeL1TxsNum)

 	if err := s.updateCurrentNextSlotIfSync(true, nil); err != nil {
@@ -761,19 +800,14 @@ func (s *Synchronizer) rollupSync(ethBlock *common.Block) (*common.RollupData, e

 	// Get rollup events in the block, and make sure the block hash matches
 	// the expected one.
-	rollupEvents, blockHash, err := s.ethClient.RollupEventsByBlock(blockNum)
+	rollupEvents, err := s.ethClient.RollupEventsByBlock(blockNum, &ethBlock.Hash)
 	if err != nil {
 		return nil, tracerr.Wrap(err)
 	}
 	// No events in this block
-	if blockHash == nil {
+	if rollupEvents == nil {
 		return &rollupData, nil
 	}
-	if *blockHash != ethBlock.Hash {
-		log.Errorw("Block hash mismatch in Rollup events", "expected", ethBlock.Hash.String(),
-			"got", blockHash.String())
-		return nil, tracerr.Wrap(eth.ErrBlockHashMismatchEvent)
-	}

 	var nextForgeL1TxsNum int64 // forgeL1TxsNum for the next L1Batch
 	nextForgeL1TxsNumPtr, err := s.historyDB.GetLastL1TxsNum()
@@ -801,7 +835,7 @@ func (s *Synchronizer) rollupSync(ethBlock *common.Block) (*common.RollupData, e
 		forgeBatchArgs, sender, err := s.ethClient.RollupForgeBatchArgs(evtForgeBatch.EthTxHash,
 			evtForgeBatch.L1UserTxsLen)
 		if err != nil {
-			return nil, tracerr.Wrap(err)
+			return nil, tracerr.Wrap(fmt.Errorf("RollupForgeBatchArgs: %w", err))
 		}

 		batchNum := common.BatchNum(evtForgeBatch.BatchNum)
@@ -884,6 +918,10 @@ func (s *Synchronizer) rollupSync(ethBlock *common.Block) (*common.RollupData, e
 		if err != nil {
 			return nil, tracerr.Wrap(err)
 		}
+		if s.stateDB.CurrentBatch() != batchNum {
+			return nil, tracerr.Wrap(fmt.Errorf("stateDB.BatchNum (%v) != evtForgeBatch.BatchNum = (%v)",
+				s.stateDB.CurrentBatch(), batchNum))
+		}

 		// Transform processed PoolL2 txs to L2 and store in BatchData
 		l2Txs, err := common.PoolL2TxsToL2Txs(poolL2Txs) // NOTE: This is a big uggly, find a better way
@@ -1066,19 +1104,14 @@ func (s *Synchronizer) auctionSync(ethBlock *common.Block) (*common.AuctionData,
 	var auctionData = common.NewAuctionData()

 	// Get auction events in the block
-	auctionEvents, blockHash, err := s.ethClient.AuctionEventsByBlock(blockNum)
+	auctionEvents, err := s.ethClient.AuctionEventsByBlock(blockNum, &ethBlock.Hash)
 	if err != nil {
 		return nil, tracerr.Wrap(err)
 	}
 	// No events in this block
-	if blockHash == nil {
+	if auctionEvents == nil {
 		return &auctionData, nil
 	}
-	if *blockHash != ethBlock.Hash {
-		log.Errorw("Block hash mismatch in Auction events", "expected", ethBlock.Hash.String(),
-			"got", blockHash.String())
-		return nil, tracerr.Wrap(eth.ErrBlockHashMismatchEvent)
-	}

 	// Get bids
 	for _, evt := range auctionEvents.NewBid {
@@ -1168,19 +1201,14 @@ func (s *Synchronizer) wdelayerSync(ethBlock *common.Block) (*common.WDelayerDat
 	wDelayerData := common.NewWDelayerData()

 	// Get wDelayer events in the block
-	wDelayerEvents, blockHash, err := s.ethClient.WDelayerEventsByBlock(blockNum)
+	wDelayerEvents, err := s.ethClient.WDelayerEventsByBlock(blockNum, &ethBlock.Hash)
 	if err != nil {
 		return nil, tracerr.Wrap(err)
 	}
 	// No events in this block
-	if blockHash == nil {
+	if wDelayerEvents == nil {
 		return &wDelayerData, nil
 	}
-	if *blockHash != ethBlock.Hash {
-		log.Errorw("Block hash mismatch in WDelayer events", "expected", ethBlock.Hash.String(),
-			"got", blockHash.String())
-		return nil, tracerr.Wrap(eth.ErrBlockHashMismatchEvent)
-	}

 	for _, evt := range wDelayerEvents.Deposit {
 		wDelayerData.Deposits = append(wDelayerData.Deposits, common.WDelayerTransfer{
--- a/test/ethclient.go
+++ b/test/ethclient.go
@@ -1116,15 +1116,20 @@ func (c *Client) RollupConstants() (*common.RollupConstants, error) {
 }

 // RollupEventsByBlock returns the events in a block that happened in the Rollup Smart Contract
-func (c *Client) RollupEventsByBlock(blockNum int64) (*eth.RollupEvents, *ethCommon.Hash, error) {
+func (c *Client) RollupEventsByBlock(blockNum int64,
+	blockHash *ethCommon.Hash) (*eth.RollupEvents, error) {
 	c.rw.RLock()
 	defer c.rw.RUnlock()

 	block, ok := c.blocks[blockNum]
 	if !ok {
-		return nil, nil, tracerr.Wrap(fmt.Errorf("Block %v doesn't exist", blockNum))
+		return nil, tracerr.Wrap(fmt.Errorf("Block %v doesn't exist", blockNum))
 	}
-	return &block.Rollup.Events, &block.Eth.Hash, nil
+	if blockHash != nil && *blockHash != block.Eth.Hash {
+		return nil, tracerr.Wrap(fmt.Errorf("Hash mismatch, requested %v got %v",
+			blockHash, block.Eth.Hash))
+	}
+	return &block.Rollup.Events, nil
 }

 // RollupEventInit returns the initialize event with its corresponding block number
@@ -1573,15 +1578,20 @@ func (c *Client) AuctionConstants() (*common.AuctionConstants, error) {
 }

 // AuctionEventsByBlock returns the events in a block that happened in the Auction Smart Contract
-func (c *Client) AuctionEventsByBlock(blockNum int64) (*eth.AuctionEvents, *ethCommon.Hash, error) {
+func (c *Client) AuctionEventsByBlock(blockNum int64,
+	blockHash *ethCommon.Hash) (*eth.AuctionEvents, error) {
 	c.rw.RLock()
 	defer c.rw.RUnlock()

 	block, ok := c.blocks[blockNum]
 	if !ok {
-		return nil, nil, tracerr.Wrap(fmt.Errorf("Block %v doesn't exist", blockNum))
+		return nil, tracerr.Wrap(fmt.Errorf("Block %v doesn't exist", blockNum))
 	}
-	return &block.Auction.Events, &block.Eth.Hash, nil
+	if blockHash != nil && *blockHash != block.Eth.Hash {
+		return nil, tracerr.Wrap(fmt.Errorf("Hash mismatch, requested %v got %v",
+			blockHash, block.Eth.Hash))
+	}
+	return &block.Auction.Events, nil
 }

 // AuctionEventInit returns the initialize event with its corresponding block number
@@ -1789,15 +1799,20 @@ func (c *Client) WDelayerEscapeHatchWithdrawal(to, token ethCommon.Address, amou
 }

 // WDelayerEventsByBlock returns the events in a block that happened in the WDelayer Contract
-func (c *Client) WDelayerEventsByBlock(blockNum int64) (*eth.WDelayerEvents, *ethCommon.Hash, error) {
+func (c *Client) WDelayerEventsByBlock(blockNum int64,
+	blockHash *ethCommon.Hash) (*eth.WDelayerEvents, error) {
 	c.rw.RLock()
 	defer c.rw.RUnlock()

 	block, ok := c.blocks[blockNum]
 	if !ok {
-		return nil, nil, tracerr.Wrap(fmt.Errorf("Block %v doesn't exist", blockNum))
+		return nil, tracerr.Wrap(fmt.Errorf("Block %v doesn't exist", blockNum))
 	}
-	return &block.WDelayer.Events, &block.Eth.Hash, nil
+	if blockHash != nil && *blockHash != block.Eth.Hash {
+		return nil, tracerr.Wrap(fmt.Errorf("Hash mismatch, requested %v got %v",
+			blockHash, block.Eth.Hash))
+	}
+	return &block.WDelayer.Events, nil
 }

 // WDelayerConstants returns the Constants of the WDelayer Contract
--- a/test/ethclient_test.go
+++ b/test/ethclient_test.go
@@ -130,7 +130,7 @@ func TestClientAuction(t *testing.T) {
 	blockNum, err := c.EthLastBlock()
 	require.Nil(t, err)

-	auctionEvents, _, err := c.AuctionEventsByBlock(blockNum)
+	auctionEvents, err := c.AuctionEventsByBlock(blockNum, nil)
 	require.Nil(t, err)
 	assert.Equal(t, 2, len(auctionEvents.NewBid))
 }
@@ -171,7 +171,7 @@ func TestClientRollup(t *testing.T) {

 	blockNum, err := c.EthLastBlock()
 	require.Nil(t, err)
-	rollupEvents, _, err := c.RollupEventsByBlock(blockNum)
+	rollupEvents, err := c.RollupEventsByBlock(blockNum, nil)
 	require.Nil(t, err)
 	assert.Equal(t, N, len(rollupEvents.L1UserTx))
 	assert.Equal(t, 1, len(rollupEvents.AddToken))
@@ -192,7 +192,7 @@ func TestClientRollup(t *testing.T) {

 	blockNumA, err := c.EthLastBlock()
 	require.Nil(t, err)
-	rollupEvents, hashA, err := c.RollupEventsByBlock(blockNumA)
+	rollupEvents, err = c.RollupEventsByBlock(blockNumA, nil)
 	require.Nil(t, err)
 	assert.Equal(t, 0, len(rollupEvents.L1UserTx))
 	assert.Equal(t, 0, len(rollupEvents.AddToken))
@@ -205,14 +205,14 @@ func TestClientRollup(t *testing.T) {

 	blockNumB, err := c.EthLastBlock()
 	require.Nil(t, err)
-	rollupEvents, hashB, err := c.RollupEventsByBlock(blockNumA)
+	rollupEventsB, err := c.RollupEventsByBlock(blockNumA, nil)
 	require.Nil(t, err)
-	assert.Equal(t, 0, len(rollupEvents.L1UserTx))
-	assert.Equal(t, 0, len(rollupEvents.AddToken))
-	assert.Equal(t, 0, len(rollupEvents.ForgeBatch))
+	assert.Equal(t, 0, len(rollupEventsB.L1UserTx))
+	assert.Equal(t, 0, len(rollupEventsB.AddToken))
+	assert.Equal(t, 0, len(rollupEventsB.ForgeBatch))

 	assert.Equal(t, blockNumA, blockNumB)
-	assert.NotEqual(t, hashA, hashB)
+	assert.NotEqual(t, rollupEvents, rollupEventsB)

 	// Forge again
 	rollupForgeBatchArgs0 := &eth.RollupForgeBatchArgs{
@@ -232,7 +232,7 @@ func TestClientRollup(t *testing.T) {

 	blockNum, err = c.EthLastBlock()
 	require.Nil(t, err)
-	rollupEvents, _, err = c.RollupEventsByBlock(blockNum)
+	rollupEvents, err = c.RollupEventsByBlock(blockNum, nil)
 	require.Nil(t, err)

 	rollupForgeBatchArgs1, sender, err := c.RollupForgeBatchArgs(rollupEvents.ForgeBatch[0].EthTxHash,