diff --git a/cmd/mongo/oplog_push.go b/cmd/mongo/oplog_push.go
index 6f699e160..c9b0fc675 100644
--- a/cmd/mongo/oplog_push.go
+++ b/cmd/mongo/oplog_push.go
@@ -199,7 +199,7 @@ func buildOplogPushRunArgs() (args oplogPushRunArgs, err error) {
 		return
 	}
 
-	return
+	return args, nil
 }
 
 type oplogPushStatsArgs struct {
diff --git a/cmd/mongo/oplog_replay.go b/cmd/mongo/oplog_replay.go
index c2a14deca..dafe5a248 100644
--- a/cmd/mongo/oplog_replay.go
+++ b/cmd/mongo/oplog_replay.go
@@ -96,24 +96,24 @@ func buildOplogReplayRunArgs(cmdargs []string) (args oplogReplayRunArgs, err err
 	return args, nil
 }
 
-func processArg(arg string, downloader *archive.StorageDownloader) (models.Timestamp, error) {
-	switch arg {
-	case internal.LatestString:
-		return downloader.LastKnownArchiveTS()
-	case LatestBackupString:
-		lastBackupName, err := downloader.LastBackupName()
-		if err != nil {
-			return models.Timestamp{}, err
-		}
-		backupMeta, err := downloader.BackupMeta(lastBackupName)
-		if err != nil {
-			return models.Timestamp{}, err
-		}
-		return models.TimestampFromBson(backupMeta.MongoMeta.BackupLastTS), nil
-	default:
-		return models.TimestampFromStr(arg)
-	}
-}
+//func processArg(arg string, downloader *archive.StorageDownloader) (models.Timestamp, error) {
+//	switch arg {
+//	case internal.LatestString:
+//		return downloader.LastKnownArchiveTS()
+//	case LatestBackupString:
+//		lastBackupName, err := downloader.LastBackupName()
+//		if err != nil {
+//			return models.Timestamp{}, err
+//		}
+//		backupMeta, err := downloader.BackupMeta(lastBackupName)
+//		if err != nil {
+//			return models.Timestamp{}, err
+//		}
+//		return models.TimestampFromBson(backupMeta.MongoMeta.BackupLastTS), nil
+//	default:
+//		return models.TimestampFromStr(arg)
+//	}
+//}
 
 func runOplogReplay(ctx context.Context, replayArgs oplogReplayRunArgs) error {
 	tracelog.DebugLogger.Printf("starting replay with arguments: %+v", replayArgs)
@@ -138,8 +138,8 @@ func runOplogReplay(ctx context.Context, replayArgs oplogReplayRunArgs) error {
 		return err
 	}
 
-	filterList := shake.OplogFilterChain{new(shake.AutologousFilter), new(shake.NoopFilter), new(shake.DDLFilter)}
-	dbApplier := oplog.NewDBApplier(mongoClient, false, replayArgs.ignoreErrCodes, replayArgs.dbNode, filterList)
+	filterList := shake.OplogFilterChain{new(shake.AutologousFilter), new(shake.NoopFilter)}
+	dbApplier := oplog.NewDBApplier(mongoClient, true, replayArgs.ignoreErrCodes, replayArgs.dbNode, filterList)
 	oplogApplier := stages.NewGenericApplier(dbApplier)
 
 	// set up storage downloader client
diff --git a/internal/databases/mongo/archive/loader.go b/internal/databases/mongo/archive/loader.go
index 2f5cd4dee..722254470 100644
--- a/internal/databases/mongo/archive/loader.go
+++ b/internal/databases/mongo/archive/loader.go
@@ -132,7 +132,8 @@ func (sd *StorageDownloader) LastBackupName() (string, error) {
 
 // DownloadOplogArchive downloads, decompresses and decrypts (if needed) oplog archive.
 func (sd *StorageDownloader) DownloadOplogArchive(arch models.Archive, writeCloser io.WriteCloser) error {
-	return internal.DownloadFile(internal.NewFolderReader(sd.oplogsFolder), arch.DBNodeSpecificFileName(sd.GetNodeSpecificDownloader()), arch.Extension(), writeCloser)
+	return internal.DownloadFile(internal.NewFolderReader(sd.oplogsFolder),
+		arch.DBNodeSpecificFileName(sd.GetNodeSpecificDownloader()), arch.Extension(), writeCloser)
 }
 
 // ListOplogArchives fetches all oplog archives existed in storage.
@@ -323,7 +324,8 @@ func (su *StorageUploader) UploadGapArchive(archErr error, firstTS, lastTS model
 		return fmt.Errorf("can not build archive: %w", err)
 	}
 
-	if err := su.PushStreamToDestination(context.Background(), strings.NewReader(archErr.Error()), arch.DBNodeSpecificFileName(su.dbNode)); err != nil {
+	if err := su.PushStreamToDestination(context.Background(), strings.NewReader(archErr.Error()),
+		arch.DBNodeSpecificFileName(su.dbNode)); err != nil {
 		return fmt.Errorf("error while uploading stream: %w", err)
 	}
 	return nil
diff --git a/internal/databases/mongo/client/client.go b/internal/databases/mongo/client/client.go
index 9bec7774e..9ffc589fc 100644
--- a/internal/databases/mongo/client/client.go
+++ b/internal/databases/mongo/client/client.go
@@ -350,10 +350,6 @@ func (mc *MongoClient) ApplyOp(ctx context.Context, dbop db.Oplog) error {
 	cmd[0] = bson.E{Key: "applyOps", Value: []interface{}{op}}
 	apply := mc.c.Database("admin").RunCommand(ctx, cmd)
 	if err := apply.Err(); err != nil {
-		fmt.Println("-------------------------------------", err)
-		if mongo.IsDuplicateKeyError(err) {
-			return nil
-		}
 		return err
 	}
 	resp := CmdResponse{}
diff --git a/internal/databases/mongo/oplog/applier.go b/internal/databases/mongo/oplog/applier.go
index 55c1c7e34..1f78d7cfc 100644
--- a/internal/databases/mongo/oplog/applier.go
+++ b/internal/databases/mongo/oplog/applier.go
@@ -13,7 +13,6 @@ import (
 	"go.mongodb.org/mongo-driver/bson"
 	"go.mongodb.org/mongo-driver/mongo"
 	"io"
-	"strings"
 )
 
 type TypeAssertionError struct {
@@ -83,8 +82,10 @@ type DBApplier struct {
 }
 
 // NewDBApplier builds DBApplier with given args.
-func NewDBApplier(m client.MongoDriver, preserveUUID bool, ignoreErrCodes map[string][]int32, node string, filterList shake.OplogFilterChain) *DBApplier {
-	return &DBApplier{db: m, txnBuffer: txn.NewBuffer(), preserveUUID: preserveUUID, applyIgnoreErrorCodes: ignoreErrCodes, dbNode: node, filterList: filterList}
+func NewDBApplier(m client.MongoDriver, preserveUUID bool, ignoreErrCodes map[string][]int32,
+	node string, filterList shake.OplogFilterChain) *DBApplier {
+	return &DBApplier{db: m, txnBuffer: txn.NewBuffer(), preserveUUID: preserveUUID,
+		applyIgnoreErrorCodes: ignoreErrCodes, dbNode: node, filterList: filterList}
 }
 
 func (ap *DBApplier) Apply(ctx context.Context, opr models.Oplog) error {
@@ -99,17 +100,12 @@ func (ap *DBApplier) Apply(ctx context.Context, opr models.Oplog) error {
 		return nil
 	}
 
-	if strings.HasPrefix(ap.dbNode, "shard") {
+	if ap.dbNode != "configsvr" {
 		if ap.filterList.IterateFilter(&op) {
 			return nil
 		}
 	}
 
-	//if err := ap.shouldSkip(op.Operation, op.Namespace); err != nil {
-	//	tracelog.DebugLogger.Printf("skipping op %+v due to: %+v", op, err)
-	//	return nil
-	//}
-
 	meta, err := txn.NewMeta(op)
 	if err != nil {
 		return fmt.Errorf("can not extract op metadata: %w", err)
@@ -142,26 +138,15 @@ func (ap *DBApplier) Close(ctx context.Context) error {
 	return nil
 }
 
-func (ap *DBApplier) shouldSkip(op, ns string) error {
-	if op == "n" {
-		return fmt.Errorf("noop op")
-	}
-
-	// sharded clusters are not supported yet
-	if (strings.HasPrefix(ns, "config.") || strings.HasPrefix(ns, "admin.")) && ap.dbNode != "configsvr" {
-		return fmt.Errorf("config database op")
-	}
-
-	return nil
-}
-
 // shouldIgnore checks if error should be ignored
 func (ap *DBApplier) shouldIgnore(op string, err error) bool {
 	ce, ok := err.(mongo.CommandError)
 	if !ok {
 		return false
 	}
-
+	if mongo.IsDuplicateKeyError(err) {
+		return true
+	}
 	ignoreErrorCodes, ok := ap.applyIgnoreErrorCodes[op]
 	if !ok {
 		return false
@@ -273,8 +258,8 @@ func indexSpecFromCommitIndexBuilds(op db.Oplog) (string, []client.IndexDocument
 				if !ok {
 					return "", nil, NewTypeAssertionError("bson.D", fmt.Sprintf("indexes[%d]", i), elemE.Value)
 				}
-				for i := range elements {
-					elemE = elements[i]
+				for j := range elements {
+					elemE = elements[j]
 					if elemE.Key == "key" {
 						if indexSpecs[i].Key, ok = elemE.Value.(bson.D); !ok {
 							return "", nil, NewTypeAssertionError("bson.D", "key", elemE.Value)
diff --git a/internal/databases/mongo/shake/filter.go b/internal/databases/mongo/shake/filter.go
index 575ab7f0b..7da4a8c60 100644
--- a/internal/databases/mongo/shake/filter.go
+++ b/internal/databases/mongo/shake/filter.go
@@ -1,14 +1,13 @@
 package shake
 
 import (
-	"fmt"
 	"github.com/mongodb/mongo-tools-common/db"
 	"github.com/wal-g/tracelog"
 	"reflect"
 	"strings"
 )
 
-// OplogFilter: AutologousFilter, NoopFilter, DDLFilter
+// OplogFilter: AutologousFilter, NoopFilter
 type OplogFilter interface {
 	Filter(log *db.Oplog) bool
 }
@@ -28,21 +27,16 @@ type AutologousFilter struct {
 }
 
 func (filter *AutologousFilter) Filter(log *db.Oplog) bool {
-
 	// Filter out unnecessary commands
 	if operation, found := ExtraCommandName(log.Object); found {
-		fmt.Printf("unnecessary commands. operation: %v found: %v\n", operation)
 		if IsNeedFilterCommand(operation) {
 			return true
 		}
 	}
-
-	// for namespace. we filter noop operation and collection name
-	// that are admin, local, mongoshake, mongoshake_conflict
 	return filter.FilterNs(log.Namespace)
 }
 
-// namespace should be filtered.
+// NsShouldBeIgnore for namespaces should be filtered.
 // key: ns, value: true means prefix, false means contain
 var NsShouldBeIgnore = map[string]bool{
 	"admin.":       true,
@@ -51,32 +45,33 @@ var NsShouldBeIgnore = map[string]bool{
 	"system.views": false,
 }
 
-// namespace should not be filtered.
 // NsShouldNotBeIgnore has a higher priority than NsShouldBeIgnore
 // key: ns, value: true means prefix, false means contain
 var NsShouldNotBeIgnore = map[string]bool{
-	"admin.$cmd": true,
+	"admin.$cmd":         true,
+	"admin.system.users": false,
+	"admin.system.roles": false,
 }
 
 func (filter *AutologousFilter) FilterNs(namespace string) bool {
 	// for namespace. we filter noop operation and collection name
-	// that are admin, local, config, mongoshake, mongoshake_conflict
+	// that are admin, local, config
 
 	// v2.4.13, don't filter admin.$cmd which may include transaction
+	// we don't filter admin.system.users and admin.system.roles to retrieve roles and users
 	for key, val := range NsShouldNotBeIgnore {
-		if val == true && strings.HasPrefix(namespace, key) {
+		if val && strings.HasPrefix(namespace, key) {
 			return false
 		}
-		if val == false && strings.Contains(namespace, key) {
+		if !val && strings.Contains(namespace, key) {
 			return false
 		}
 	}
-
 	for key, val := range NsShouldBeIgnore {
-		if val == true && strings.HasPrefix(namespace, key) {
+		if val && strings.HasPrefix(namespace, key) {
 			return true
 		}
-		if val == false && strings.Contains(namespace, key) {
+		if !val && strings.Contains(namespace, key) {
 			return true
 		}
 	}
@@ -90,10 +85,11 @@ func (filter *NoopFilter) Filter(log *db.Oplog) bool {
 	return log.Operation == "n"
 }
 
-type DDLFilter struct {
-}
-
-func (filter *DDLFilter) Filter(log *db.Oplog) bool {
-	operation, _ := ExtraCommandName(log.Object)
-	return log.Operation == "c" && operation != "applyOps" && operation != "create" || strings.HasSuffix(log.Namespace, "system.indexes")
-}
+//type DDLFilter struct {
+//}
+//
+//func (filter *DDLFilter) Filter(log *db.Oplog) bool {
+//	//operation, _ := ExtraCommandName(log.Object)
+//	//return log.Operation == "c" && operation != "applyOps" && operation != "create" || strings.HasSuffix(log.Namespace, "system.indexes")
+//	return false
+//}
diff --git a/internal/databases/mongo/stages/applier.go b/internal/databases/mongo/stages/applier.go
index 8085be2b4..b1883b5d8 100644
--- a/internal/databases/mongo/stages/applier.go
+++ b/internal/databases/mongo/stages/applier.go
@@ -34,7 +34,6 @@ func NewGenericApplier(applier oplog.Applier) *GenericApplier {
 
 // Apply runs working cycle that applies oplog records.
 func (dba *GenericApplier) Apply(ctx context.Context, ch chan *models.Oplog) (chan error, error) {
-
 	errc := make(chan error)
 	go func() {
 		defer close(errc)
diff --git a/internal/databases/mysql/binlog_fetch_handler.go b/internal/databases/mysql/binlog_fetch_handler.go
index 3bb9ef462..19baf8c6a 100644
--- a/internal/databases/mysql/binlog_fetch_handler.go
+++ b/internal/databases/mysql/binlog_fetch_handler.go
@@ -47,11 +47,11 @@ func HandleBinlogFetch(folder storage.Folder, backupName string, untilTS string,
 	tracelog.ErrorLogger.FatalOnError(err)
 	var startTS, endTS, endBinlogTS time.Time
 	if skipStartTime {
-		startTS, endTS, endBinlogTS, err = getEndTimestamps(folder, untilTS, untilBinlogLastModifiedTS)
+		startTS, endTS, endBinlogTS, err = getEndTimestamps(untilTS, untilBinlogLastModifiedTS)
 	} else {
 		startTS, endTS, endBinlogTS, err = getTimestamps(folder, backupName, untilTS, untilBinlogLastModifiedTS)
-		tracelog.ErrorLogger.FatalOnError(err)
 	}
+	tracelog.ErrorLogger.FatalOnError(err)
 
 	handler := newIndexHandler(dstDir)
 
diff --git a/internal/databases/mysql/binlog_replay_handler.go b/internal/databases/mysql/binlog_replay_handler.go
index 118c5e2fd..c8ea17008 100644
--- a/internal/databases/mysql/binlog_replay_handler.go
+++ b/internal/databases/mysql/binlog_replay_handler.go
@@ -112,7 +112,7 @@ func getTimestamps(folder storage.Folder, backupName, untilTS, untilBinlogLastMo
 	return startTS, endTS, endBinlogTS, nil
 }
 
-func getEndTimestamps(folder storage.Folder, untilTS, untilBinlogLastModifiedTS string) (time.Time, time.Time, time.Time, error) {
+func getEndTimestamps(untilTS, untilBinlogLastModifiedTS string) (time.Time, time.Time, time.Time, error) {
 	endTS, err := utility.ParseUntilTS(untilTS)
 	if err != nil {
 		return time.Time{}, time.Time{}, time.Time{}, err