@BeforeClass
  public static void setupTest() throws Exception {
    // Set createWALDir to true and use default values for other options.
    UTIL.startMiniCluster(StartTestingClusterOption.builder().createWALDir(true).build());
  }
Test the master filesystem in a local cluster
hbase-server/src/test/java/org/apache/hadoop/hbase/master/TestMasterFileSystemWithWALDir.java