diff --git a/internal/datacoord/server.go b/internal/datacoord/server.go
index bb9f4b10b1..19c7757397 100644
--- a/internal/datacoord/server.go
+++ b/internal/datacoord/server.go
@@ -804,16 +804,9 @@ func (s *Server) GetVChanPositions(channel string, collectionID UniqueID, seekFr
 	}
 	// use collection start position when segment position is not found
 	if seekPosition == nil {
-		coll := s.meta.GetCollection(collectionID)
-		if coll != nil {
-			for _, sp := range coll.GetStartPositions() {
-				if sp.GetKey() == rootcoord.ToPhysicalChannel(channel) {
-					seekPosition = &internalpb.MsgPosition{
-						ChannelName: channel,
-						MsgID:       sp.GetData(),
-					}
-				}
-			}
+		collection := s.GetCollection(s.ctx, collectionID)
+		if collection != nil {
+			seekPosition = getCollectionStartPosition(channel, collection)
 		}
 	}
 
@@ -826,6 +819,19 @@ func (s *Server) GetVChanPositions(channel string, collectionID UniqueID, seekFr
 	}
 }
 
+func getCollectionStartPosition(channel string, collectionInfo *datapb.CollectionInfo) *internalpb.MsgPosition {
+	for _, sp := range collectionInfo.GetStartPositions() {
+		if sp.GetKey() != rootcoord.ToPhysicalChannel(channel) {
+			continue
+		}
+		return &internalpb.MsgPosition{
+			ChannelName: channel,
+			MsgID:       sp.GetData(),
+		}
+	}
+	return nil
+}
+
 // trimSegmentInfo returns a shallow copy of datapb.SegmentInfo and sets ALL binlog info to nil
 func trimSegmentInfo(info *datapb.SegmentInfo) *datapb.SegmentInfo {
 	return &datapb.SegmentInfo{
@@ -841,3 +847,16 @@ func trimSegmentInfo(info *datapb.SegmentInfo) *datapb.SegmentInfo {
 		DmlPosition:    info.DmlPosition,
 	}
 }
+
+func (s *Server) GetCollection(ctx context.Context, collectionID UniqueID) *datapb.CollectionInfo {
+	coll := s.meta.GetCollection(collectionID)
+	if coll != nil {
+		return coll
+	}
+	err := s.loadCollectionFromRootCoord(ctx, collectionID)
+	if err != nil {
+		log.Warn("failed to load collection from RootCoord", zap.Int64("collectionID", collectionID), zap.Error(err))
+	}
+
+	return s.meta.GetCollection(collectionID)
+}
diff --git a/internal/datacoord/services.go b/internal/datacoord/services.go
index 0a484b432d..90cab67e96 100644
--- a/internal/datacoord/services.go
+++ b/internal/datacoord/services.go
@@ -114,13 +114,8 @@ func (s *Server) AssignSegmentID(ctx context.Context, req *datapb.AssignSegmentI
 			zap.String("channelName", r.GetChannelName()),
 			zap.Uint32("count", r.GetCount()))
 
-		if coll := s.meta.GetCollection(r.CollectionID); coll == nil {
-			if err := s.loadCollectionFromRootCoord(ctx, r.CollectionID); err != nil {
-				log.Error("load collection from rootcoord error",
-					zap.Int64("collectionID", r.CollectionID),
-					zap.Error(err))
-				continue
-			}
+		if coll := s.GetCollection(ctx, r.CollectionID); coll == nil {
+			continue
 		}
 
 		s.cluster.Watch(r.ChannelName, r.CollectionID)