diff --git a/hadoop-hdfs-project/hadoop-hdfs-client/src/main/proto/hdfs.proto b/hadoop-hdfs-project/hadoop-hdfs-client/src/main/proto/hdfs.proto
index c07dd9e..1b82272 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-client/src/main/proto/hdfs.proto
+++ b/hadoop-hdfs-project/hadoop-hdfs-client/src/main/proto/hdfs.proto
@@ -180,7 +180,7 @@
 }
 
 message StorageTypeQuotaInfoProto {
-  required StorageTypeProto type = 1;
+  optional StorageTypeProto type = 1 [default = DISK];
   required uint64 quota = 2;
   required uint64 consumed = 3;
 }