diff --git a/cmd/tools/migration/meta/210_to_220.go b/cmd/tools/migration/meta/210_to_220.go
index 0b40a693f6..4e4553407a 100644
--- a/cmd/tools/migration/meta/210_to_220.go
+++ b/cmd/tools/migration/meta/210_to_220.go
@@ -3,6 +3,7 @@ package meta
 import (
 	"fmt"
 	"sort"
+	"strconv"
 	"strings"
 
 	"github.com/milvus-io/milvus-proto/go-api/commonpb"
@@ -172,12 +173,16 @@ func combineToCollectionIndexesMeta220(fieldIndexes FieldIndexes210, collectionI
 			for k, v := range newIndexParamsMap {
 				newIndexParams = append(newIndexParams, &commonpb.KeyValuePair{Key: k, Value: v})
 			}
+			newIndexName := indexInfo.GetIndexName()
+			if newIndexName == "_default_idx" {
+				newIndexName = "_default_idx_" + strconv.FormatInt(index.GetFiledID(), 10)
+			}
 			record := &model.Index{
 				TenantID:        "", // TODO: how to set this if we support mysql later?
 				CollectionID:    collectionID,
 				FieldID:         index.GetFiledID(),
 				IndexID:         index.GetIndexID(),
-				IndexName:       indexInfo.GetIndexName(),
+				IndexName:       newIndexName,
 				IsDeleted:       indexInfo.GetDeleted(),
 				CreateTime:      indexInfo.GetCreateTime(),
 				TypeParams:      field.GetTypeParams(),
diff --git a/internal/proxy/task_index.go b/internal/proxy/task_index.go
index 94c533eb41..4482a9903d 100644
--- a/internal/proxy/task_index.go
+++ b/internal/proxy/task_index.go
@@ -498,6 +498,9 @@ func (dit *dropIndexTask) PreExecute(ctx context.Context) error {
 	dit.Base.MsgType = commonpb.MsgType_DropIndex
 	dit.Base.SourceID = Params.ProxyCfg.GetNodeID()
 
+	if dit.GetIndexName() == "" {
+		return errors.New("IndexName is not specified")
+	}
 	collName, fieldName := dit.CollectionName, dit.FieldName
 
 	if err := validateCollectionName(collName); err != nil {
@@ -508,10 +511,6 @@ func (dit *dropIndexTask) PreExecute(ctx context.Context) error {
 		return err
 	}
 
-	if dit.IndexName == "" {
-		dit.IndexName = Params.CommonCfg.DefaultIndexName
-	}
-
 	collID, err := globalMetaCache.GetCollectionID(ctx, dit.CollectionName)
 	if err != nil {
 		return err
diff --git a/internal/proxy/task_index_test.go b/internal/proxy/task_index_test.go
index ac2bf5aa20..06b5d7616f 100644
--- a/internal/proxy/task_index_test.go
+++ b/internal/proxy/task_index_test.go
@@ -96,7 +96,7 @@ func TestDropIndexTask_PreExecute(t *testing.T) {
 	collectionName := "collection1"
 	collectionID := UniqueID(1)
 	fieldName := "field1"
-	indexName := ""
+	indexName := "_default_idx_101"
 
 	Params.Init()
 	showCollectionMock := func(ctx context.Context, request *querypb.ShowCollectionsRequest) (*querypb.ShowCollectionsResponse, error) {
diff --git a/tests/python_client/requirements.txt b/tests/python_client/requirements.txt
index 6c1cb9e302..cfacc95d81 100644
--- a/tests/python_client/requirements.txt
+++ b/tests/python_client/requirements.txt
@@ -12,7 +12,7 @@ allure-pytest==2.7.0
 pytest-print==0.2.1
 pytest-level==0.1.1
 pytest-xdist==2.5.0
-pymilvus==2.2.0.dev67
+pymilvus==2.2.0.dev68
 pytest-rerunfailures==9.1.1
 git+https://github.com/Projectplace/pytest-tags
 ndg-httpsclient