HDFS-9237. NPE at TestDataNodeVolumeFailureToleration#tearDown. Contributed by Brahma Reddy Battula.

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -2074,6 +2074,9 @@ Release 2.8.0 - UNRELEASED
     HDFS-9157. [OEV and OIV] : Unnecessary parsing for mandatory arguements if
     '-h' option is specified as the only option (nijel via vinayakumarb)
 
+    HDFS-9237. NPE at TestDataNodeVolumeFailureToleration#tearDown.
+    (Brahma Reddy Battula via ozawa)
+
 Release 2.7.2 - UNRELEASED
 
   INCOMPATIBLE CHANGES

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/TestDataNodeVolumeFailureToleration.java

@@ -76,7 +76,9 @@ public class TestDataNodeVolumeFailureToleration {
 
   @After
   public void tearDown() throws Exception {
-    cluster.shutdown();
+    if (cluster != null) {
+      cluster.shutdown();
+    }
   }
 
   /**