diff --git a/weed/server/volume_grpc_copy.go b/weed/server/volume_grpc_copy.go
index cd2b53c8a..115f57422 100644
--- a/weed/server/volume_grpc_copy.go
+++ b/weed/server/volume_grpc_copy.go
@@ -61,12 +61,11 @@ func (vs *VolumeServer) VolumeCopy(ctx context.Context, req *volume_server_pb.Vo
 		volumeFileName = storage.VolumeFileName(location.Directory, volFileInfoResp.Collection, int(req.VolumeId))
 
 		// println("source:", volFileInfoResp.String())
-		// copy ecx file
-		if err := vs.doCopyFile(client, false, req.Collection, req.VolumeId, volFileInfoResp.CompactionRevision, volFileInfoResp.IdxFileSize, volumeFileName, ".idx", false, false); err != nil {
+		if err := vs.doCopyFile(client, false, req.Collection, req.VolumeId, volFileInfoResp.CompactionRevision, volFileInfoResp.DatFileSize, volumeFileName, ".dat", false, true); err != nil {
 			return err
 		}
 
-		if err := vs.doCopyFile(client, false, req.Collection, req.VolumeId, volFileInfoResp.CompactionRevision, volFileInfoResp.DatFileSize, volumeFileName, ".dat", false, true); err != nil {
+		if err := vs.doCopyFile(client, false, req.Collection, req.VolumeId, volFileInfoResp.CompactionRevision, volFileInfoResp.IdxFileSize, volumeFileName, ".idx", false, false); err != nil {
 			return err
 		}