diff --git a/hugegraph-test/src/main/java/org/apache/hugegraph/core/MultiGraphsTest.java b/hugegraph-test/src/main/java/org/apache/hugegraph/core/MultiGraphsTest.java
index cef98c3977..5dabcbdd42 100644
--- a/hugegraph-test/src/main/java/org/apache/hugegraph/core/MultiGraphsTest.java
+++ b/hugegraph-test/src/main/java/org/apache/hugegraph/core/MultiGraphsTest.java
@@ -333,7 +333,7 @@ public void testCreateGraphsWithMultiDisksForRocksDB() {
         g1.clearBackend();
 
         final HugeGraph[] g2 = new HugeGraph[1];
-        Assert.assertThrows(ConnectionException.class, () -> {
+        Assert.assertThrows(RuntimeException.class, () -> {
             g2[0] = openGraphWithBackend("g2", "rocksdb", "binary",
                                          "rocksdb.data_disks",
                                          "[g/range_int_index:rocksdb-index1]");
@@ -348,7 +348,7 @@ public void testCreateGraphsWithMultiDisksForRocksDB() {
         });
 
         final HugeGraph[] g3 = new HugeGraph[1];
-        Assert.assertThrows(ConnectionException.class, () -> {
+        Assert.assertThrows(RuntimeException.class, () -> {
             g3[0] = openGraphWithBackend("g3", "rocksdb", "binary",
                                          "rocksdb.data_disks",
                                          "[g/secondary_index:/]");
diff --git a/hugegraph-test/src/main/resources/hugegraph.properties b/hugegraph-test/src/main/resources/hugegraph.properties
index b6d52ab1f9..2a6b4f2bf9 100644
--- a/hugegraph-test/src/main/resources/hugegraph.properties
+++ b/hugegraph-test/src/main/resources/hugegraph.properties
@@ -1,7 +1,7 @@
 gremlin.graph=org.apache.hugegraph.HugeFactory
 
-backend=${backend}
-serializer=${serializer}
+backend=memory
+serializer=text
 
 store=hugegraph