Java Code Examples for org.apache.hadoop.hdfs.server.namenode.NameNodeAdapter#enterSafeMode()

@Test
public void testOpenFilesWithRename() throws Exception {
  Path path = new Path("/test");
  doWriteAndAbort(fs, path);

  // check for zero sized blocks
  Path fileWithEmptyBlock = new Path("/test/test/test4");
  fs.create(fileWithEmptyBlock);
  NamenodeProtocols nameNodeRpc = cluster.getNameNodeRpc();
  String clientName = fs.getClient().getClientName();
  // create one empty block
  nameNodeRpc.addBlock(fileWithEmptyBlock.toString(), clientName, null, null,
      INodeId.GRANDFATHER_INODE_ID, null);
  fs.createSnapshot(path, "s2");

  fs.rename(new Path("/test/test"), new Path("/test/test-renamed"));
  fs.delete(new Path("/test/test-renamed"), true);
  NameNode nameNode = cluster.getNameNode();
  NameNodeAdapter.enterSafeMode(nameNode, false);
  NameNodeAdapter.saveNamespace(nameNode);
  NameNodeAdapter.leaveSafeMode(nameNode);
  cluster.restartNameNode(true);
}
 

@Test
public void testOpenFilesWithRename() throws Exception {
  Path path = new Path("/test");
  doWriteAndAbort(fs, path);

  // check for zero sized blocks
  Path fileWithEmptyBlock = new Path("/test/test/test4");
  fs.create(fileWithEmptyBlock);
  NamenodeProtocols nameNodeRpc = cluster.getNameNodeRpc();
  String clientName = fs.getClient().getClientName();
  // create one empty block
  nameNodeRpc.addBlock(fileWithEmptyBlock.toString(), clientName, null, null,
      INodeId.GRANDFATHER_INODE_ID, null);
  fs.createSnapshot(path, "s2");

  fs.rename(new Path("/test/test"), new Path("/test/test-renamed"));
  fs.delete(new Path("/test/test-renamed"), true);
  NameNode nameNode = cluster.getNameNode();
  NameNodeAdapter.enterSafeMode(nameNode, false);
  NameNodeAdapter.saveNamespace(nameNode);
  NameNodeAdapter.leaveSafeMode(nameNode);
  cluster.restartNameNode(true);
}
 

@Test(timeout = 30000)
public void testReadSnapshotFileWithCheckpoint() throws Exception {
  Path foo = new Path("/foo");
  hdfs.mkdirs(foo);
  hdfs.allowSnapshot(foo);
  Path bar = new Path("/foo/bar");
  DFSTestUtil.createFile(hdfs, bar, 100, (short) 2, 100024L);
  hdfs.createSnapshot(foo, "s1");
  assertTrue(hdfs.delete(bar, true));

  // checkpoint
  NameNode nameNode = cluster.getNameNode();
  NameNodeAdapter.enterSafeMode(nameNode, false);
  NameNodeAdapter.saveNamespace(nameNode);
  NameNodeAdapter.leaveSafeMode(nameNode);

  // restart namenode to load snapshot files from fsimage
  cluster.restartNameNode(true);
  String snapshotPath = Snapshot.getSnapshotPath(foo.toString(), "s1/bar");
  DFSTestUtil.readFile(hdfs, new Path(snapshotPath));
}
 

/**
 * Regression test for a bug experienced while developing
 * HDFS-2742. The scenario here is:
 * - image contains some blocks
 * - edits log contains at least one block addition, followed
 *   by deletion of more blocks than were added.
 * - When node starts up, some incorrect accounting of block
 *   totals caused an assertion failure.
 */
@Test
public void testBlocksDeletedInEditLog() throws Exception {
  banner("Starting with NN0 active and NN1 standby, creating some blocks");
  // Make 4 blocks persisted in the image.
  DFSTestUtil.createFile(fs, new Path("/test"),
      4*BLOCK_SIZE, (short) 3, 1L);
  NameNodeAdapter.enterSafeMode(nn0, false);
  NameNodeAdapter.saveNamespace(nn0);
  NameNodeAdapter.leaveSafeMode(nn0);
  
  // OP_ADD for 2 blocks
  DFSTestUtil.createFile(fs, new Path("/test2"),
      2*BLOCK_SIZE, (short) 3, 1L);
  
  // OP_DELETE for 4 blocks
  fs.delete(new Path("/test"), true);

  restartActive();
}
 

@Test(timeout = 30000)
public void testReadSnapshotFileWithCheckpoint() throws Exception {
  Path foo = new Path("/foo");
  hdfs.mkdirs(foo);
  hdfs.allowSnapshot(foo);
  Path bar = new Path("/foo/bar");
  DFSTestUtil.createFile(hdfs, bar, 100, (short) 2, 100024L);
  hdfs.createSnapshot(foo, "s1");
  assertTrue(hdfs.delete(bar, true));

  // checkpoint
  NameNode nameNode = cluster.getNameNode();
  NameNodeAdapter.enterSafeMode(nameNode, false);
  NameNodeAdapter.saveNamespace(nameNode);
  NameNodeAdapter.leaveSafeMode(nameNode);

  // restart namenode to load snapshot files from fsimage
  cluster.restartNameNode(true);
  String snapshotPath = Snapshot.getSnapshotPath(foo.toString(), "s1/bar");
  DFSTestUtil.readFile(hdfs, new Path(snapshotPath));
}
 

/**
 * Restart the cluster, optionally saving a new checkpoint.
 *
 * @param checkpoint boolean true to save a new checkpoint
 * @param xattrsEnabled if true, XAttr support is enabled
 * @throws Exception if restart fails
 */
private void restart(boolean checkpoint, boolean xattrsEnabled)
    throws Exception {
  NameNode nameNode = cluster.getNameNode();
  if (checkpoint) {
    NameNodeAdapter.enterSafeMode(nameNode, false);
    NameNodeAdapter.saveNamespace(nameNode);
  }
  shutdown();
  initCluster(false, xattrsEnabled);
}
 

/**
 * Test for downloading a checkpoint made at a later checkpoint
 * from the active.
 */
@Test
public void testDownloadingLaterCheckpoint() throws Exception {
  // Roll edit logs a few times to inflate txid
  nn0.getRpcServer().rollEditLog();
  nn0.getRpcServer().rollEditLog();
  // Make checkpoint
  NameNodeAdapter.enterSafeMode(nn0, false);
  NameNodeAdapter.saveNamespace(nn0);
  NameNodeAdapter.leaveSafeMode(nn0);
  long expectedCheckpointTxId = NameNodeAdapter.getNamesystem(nn0)
    .getFSImage().getMostRecentCheckpointTxId();
  assertEquals(6, expectedCheckpointTxId);

  int rc = BootstrapStandby.run(
      new String[]{"-force"},
      cluster.getConfiguration(1));
  assertEquals(0, rc);
  
  // Should have copied over the namespace from the active
  FSImageTestUtil.assertNNHasCheckpoints(cluster, 1,
      ImmutableList.of((int)expectedCheckpointTxId));
  FSImageTestUtil.assertNNFilesMatch(cluster);

  // We should now be able to start the standby successfully.
  cluster.restartNameNode(1);
}
 

@Test
public void testTryFailoverToSafeMode() throws Exception {
  conf.set(DFSConfigKeys.DFS_HA_FENCE_METHODS_KEY, 
           TestDFSHAAdmin.getFencerTrueCommand());
  tool.setConf(conf);

  NameNodeAdapter.enterSafeMode(cluster.getNameNode(0), false);
  assertEquals(-1, runTool("-failover", "nn2", "nn1"));
  assertTrue("Bad output: " + errOutput,
      errOutput.contains("is not ready to become active: " +
          "The NameNode is in safemode"));
}
 

@Test
public void testTryFailoverToSafeMode() throws Exception {
  conf.set(DFSConfigKeys.DFS_HA_FENCE_METHODS_KEY, 
           TestDFSHAAdmin.getFencerTrueCommand());
  tool.setConf(conf);

  NameNodeAdapter.enterSafeMode(cluster.getNameNode(0), false);
  assertEquals(-1, runTool("-failover", "nn2", "nn1"));
  assertTrue("Bad output: " + errOutput,
      errOutput.contains("is not ready to become active: " +
          "The NameNode is in safemode"));
}
 

/**
 * Restart the cluster, optionally saving a new checkpoint.
 *
 * @param checkpoint boolean true to save a new checkpoint
 * @param aclsEnabled if true, ACL support is enabled
 * @throws Exception if restart fails
 */
private void restart(boolean checkpoint, boolean aclsEnabled)
    throws Exception {
  NameNode nameNode = cluster.getNameNode();
  if (checkpoint) {
    NameNodeAdapter.enterSafeMode(nameNode, false);
    NameNodeAdapter.saveNamespace(nameNode);
  }
  shutdown();
  initCluster(false, aclsEnabled);
}
 

/**
 * Delete a snapshot that is taken before a directory deletion (recursively),
 * directory diff list should be combined correctly.
 */
@Test (timeout=60000)
public void testDeleteSnapshot2() throws Exception {
  final Path root = new Path("/");

  Path dir = new Path("/dir1");
  Path file1 = new Path(dir, "file1");
  DFSTestUtil.createFile(hdfs, file1, BLOCKSIZE, REPLICATION, seed);

  hdfs.allowSnapshot(root);
  hdfs.createSnapshot(root, "s1");

  Path file2 = new Path(dir, "file2");
  DFSTestUtil.createFile(hdfs, file2, BLOCKSIZE, REPLICATION, seed);
  INodeFile file2Node = fsdir.getINode(file2.toString()).asFile();
  long file2NodeId = file2Node.getId();

  hdfs.createSnapshot(root, "s2");

  // delete directory recursively
  assertTrue(hdfs.delete(dir, true));
  assertNotNull(fsdir.getInode(file2NodeId));

  // delete second snapshot
  hdfs.deleteSnapshot(root, "s2");
  assertTrue(fsdir.getInode(file2NodeId) == null);

  NameNodeAdapter.enterSafeMode(cluster.getNameNode(), false);
  NameNodeAdapter.saveNamespace(cluster.getNameNode());

  // restart NN
  cluster.restartNameNodes();
}
 

@Test(timeout = 30000)
public void testReadRenamedSnapshotFileWithCheckpoint() throws Exception {
  final Path foo = new Path("/foo");
  final Path foo2 = new Path("/foo2");
  hdfs.mkdirs(foo);
  hdfs.mkdirs(foo2);

  hdfs.allowSnapshot(foo);
  hdfs.allowSnapshot(foo2);
  final Path bar = new Path(foo, "bar");
  final Path bar2 = new Path(foo2, "bar");
  DFSTestUtil.createFile(hdfs, bar, 100, (short) 2, 100024L);
  hdfs.createSnapshot(foo, "s1");
  // rename to another snapshottable directory and take snapshot
  assertTrue(hdfs.rename(bar, bar2));
  hdfs.createSnapshot(foo2, "s2");
  // delete the original renamed file to make sure blocks are not updated by
  // the original file
  assertTrue(hdfs.delete(bar2, true));

  // checkpoint
  NameNode nameNode = cluster.getNameNode();
  NameNodeAdapter.enterSafeMode(nameNode, false);
  NameNodeAdapter.saveNamespace(nameNode);
  NameNodeAdapter.leaveSafeMode(nameNode);
  // restart namenode to load snapshot files from fsimage
  cluster.restartNameNode(true);
  // file in first snapshot
  String barSnapshotPath = Snapshot.getSnapshotPath(foo.toString(), "s1/bar");
  DFSTestUtil.readFile(hdfs, new Path(barSnapshotPath));
  // file in second snapshot after rename+delete
  String bar2SnapshotPath = Snapshot.getSnapshotPath(foo2.toString(),
      "s2/bar");
  DFSTestUtil.readFile(hdfs, new Path(bar2SnapshotPath));
}
 

/**
 * Restart the cluster, optionally saving a new checkpoint.
 * 
 * @param checkpoint boolean true to save a new checkpoint
 * @throws Exception if restart fails
 */
private static void restart(boolean checkpoint) throws Exception {
  NameNode nameNode = cluster.getNameNode();
  if (checkpoint) {
    NameNodeAdapter.enterSafeMode(nameNode, false);
    NameNodeAdapter.saveNamespace(nameNode);
  }
  shutdown();
  initCluster(false);
}
 

/**
 * Test case for enter safemode in standby namenode, when it is already in startup safemode.
 * It is a regression test for HDFS-2747.
 */
@Test
public void testEnterSafeModeInSBNShouldNotThrowNPE() throws Exception {
  banner("Starting with NN0 active and NN1 standby, creating some blocks");
  DFSTestUtil
      .createFile(fs, new Path("/test"), 3 * BLOCK_SIZE, (short) 3, 1L);
  // Roll edit log so that, when the SBN restarts, it will load
  // the namespace during startup and enter safemode.
  nn0.getRpcServer().rollEditLog();
  banner("Creating some blocks that won't be in the edit log");
  DFSTestUtil.createFile(fs, new Path("/test2"), 5 * BLOCK_SIZE, (short) 3,
      1L);
  banner("Deleting the original blocks");
  fs.delete(new Path("/test"), true);
  banner("Restarting standby");
  restartStandby();
  FSNamesystem namesystem = nn1.getNamesystem();
  String status = namesystem.getSafemode();
  assertTrue("Bad safemode status: '" + status + "'", status
      .startsWith("Safe mode is ON."));
  NameNodeAdapter.enterSafeMode(nn1, false);
  assertTrue("Failed to enter into safemode in standby", namesystem
      .isInSafeMode());
  NameNodeAdapter.enterSafeMode(nn1, false);
  assertTrue("Failed to enter into safemode in standby", namesystem
      .isInSafeMode());
}
 

@Test
public void testGetServiceState() throws Exception {
  assertEquals(0, runTool("-getServiceState", "nn1"));
  assertEquals(0, runTool("-getServiceState", "nn2"));
  
  cluster.transitionToActive(0);
  assertEquals(0, runTool("-getServiceState", "nn1"));
  
  NameNodeAdapter.enterSafeMode(cluster.getNameNode(0), false);
  assertEquals(0, runTool("-getServiceState", "nn1"));
}
 

/**
 * Test that the delegation token secret manager only runs when the
 * NN is out of safe mode. This is because the secret manager
 * has to log to the edit log, which should not be written in
 * safe mode. Regression test for HDFS-2579.
 */
@Test
public void testDTManagerInSafeMode() throws Exception {
  cluster.startDataNodes(config, 1, true, StartupOption.REGULAR, null);
  FileSystem fs = cluster.getFileSystem();
  for (int i = 0; i < 5; i++) {
    DFSTestUtil.createFile(fs, new Path("/test-" + i), 100, (short)1, 1L);
  }
  cluster.getConfiguration(0).setInt(
      DFSConfigKeys.DFS_NAMENODE_DELEGATION_KEY_UPDATE_INTERVAL_KEY, 500); 
  cluster.getConfiguration(0).setInt(
      DFSConfigKeys.DFS_NAMENODE_SAFEMODE_EXTENSION_KEY, 30000);
  cluster.setWaitSafeMode(false);
  cluster.restartNameNode();
  NameNode nn = cluster.getNameNode();
  assertTrue(nn.isInSafeMode());
  DelegationTokenSecretManager sm =
    NameNodeAdapter.getDtSecretManager(nn.getNamesystem());
  assertFalse("Secret manager should not run in safe mode", sm.isRunning());
  
  NameNodeAdapter.leaveSafeMode(nn);
  assertTrue("Secret manager should start when safe mode is exited",
      sm.isRunning());
  
  LOG.info("========= entering safemode again");
  
  NameNodeAdapter.enterSafeMode(nn, false);
  assertFalse("Secret manager should stop again when safe mode " +
      "is manually entered", sm.isRunning());
  
  // Set the cluster to leave safemode quickly on its own.
  cluster.getConfiguration(0).setInt(
      DFSConfigKeys.DFS_NAMENODE_SAFEMODE_EXTENSION_KEY, 0);
  cluster.setWaitSafeMode(true);
  cluster.restartNameNode();
  nn = cluster.getNameNode();
  sm = NameNodeAdapter.getDtSecretManager(nn.getNamesystem());

  assertFalse(nn.isInSafeMode());
  assertTrue(sm.isRunning());
}
 

/**
 * 1. Check the blocks of old file are cleaned after creating with overwrite
 * 2. Restart NN, check the file
 * 3. Save new checkpoint and restart NN, check the file
 */
@Test(timeout = 120000)
public void testFileCreationWithOverwrite() throws Exception {
  Configuration conf = new Configuration();
  conf.setInt("dfs.blocksize", blockSize);
  MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).
      numDataNodes(3).build();
  DistributedFileSystem dfs = cluster.getFileSystem();
  try {
    dfs.mkdirs(new Path("/foo/dir"));
    String file = "/foo/dir/file";
    Path filePath = new Path(file);
    
    // Case 1: Create file with overwrite, check the blocks of old file
    // are cleaned after creating with overwrite
    NameNode nn = cluster.getNameNode();
    FSNamesystem fsn = NameNodeAdapter.getNamesystem(nn);
    BlockManager bm = fsn.getBlockManager();
    
    FSDataOutputStream out = dfs.create(filePath);
    byte[] oldData = AppendTestUtil.randomBytes(seed, fileSize);
    try {
      out.write(oldData);
    } finally {
      out.close();
    }
    
    LocatedBlocks oldBlocks = NameNodeAdapter.getBlockLocations(
        nn, file, 0, fileSize);
    assertBlocks(bm, oldBlocks, true);
    
    out = dfs.create(filePath, true);
    byte[] newData = AppendTestUtil.randomBytes(seed, fileSize);
    try {
      out.write(newData);
    } finally {
      out.close();
    }
    dfs.deleteOnExit(filePath);
    
    LocatedBlocks newBlocks = NameNodeAdapter.getBlockLocations(
        nn, file, 0, fileSize);
    assertBlocks(bm, newBlocks, true);
    assertBlocks(bm, oldBlocks, false);
    
    FSDataInputStream in = dfs.open(filePath);
    byte[] result = null;
    try {
      result = readAll(in);
    } finally {
      in.close();
    }
    Assert.assertArrayEquals(newData, result);
    
    // Case 2: Restart NN, check the file
    cluster.restartNameNode();
    nn = cluster.getNameNode();
    in = dfs.open(filePath);
    try {
      result = readAll(in);
    } finally {
      in.close();
    }
    Assert.assertArrayEquals(newData, result);
    
    // Case 3: Save new checkpoint and restart NN, check the file
    NameNodeAdapter.enterSafeMode(nn, false);
    NameNodeAdapter.saveNamespace(nn);
    cluster.restartNameNode();
    nn = cluster.getNameNode();
    
    in = dfs.open(filePath);
    try {
      result = readAll(in);
    } finally {
      in.close();
    }
    Assert.assertArrayEquals(newData, result);
  } finally {
    if (dfs != null) {
      dfs.close();
    }
    if (cluster != null) {
      cluster.shutdown();
    }
  }
}
 

/**
 * Make sure the client retries when the active NN is in safemode
 */
@Test (timeout=300000)
public void testClientRetrySafeMode() throws Exception {
  final Map<Path, Boolean> results = Collections
      .synchronizedMap(new HashMap<Path, Boolean>());
  final Path test = new Path("/test");
  // let nn0 enter safemode
  NameNodeAdapter.enterSafeMode(nn0, false);
  SafeModeInfo safeMode = (SafeModeInfo) Whitebox.getInternalState(
      nn0.getNamesystem(), "safeMode");
  Whitebox.setInternalState(safeMode, "extension", Integer.valueOf(30000));
  LOG.info("enter safemode");
  new Thread() {
    @Override
    public void run() {
      try {
        boolean mkdir = fs.mkdirs(test);
        LOG.info("mkdir finished, result is " + mkdir);
        synchronized (TestHASafeMode.this) {
          results.put(test, mkdir);
          TestHASafeMode.this.notifyAll();
        }
      } catch (Exception e) {
        LOG.info("Got Exception while calling mkdir", e);
      }
    }
  }.start();
  
  // make sure the client's call has actually been handled by the active NN
  assertFalse("The directory should not be created while NN in safemode",
      fs.exists(test));
  
  Thread.sleep(1000);
  // let nn0 leave safemode
  NameNodeAdapter.leaveSafeMode(nn0);
  LOG.info("leave safemode");
  
  synchronized (this) {
    while (!results.containsKey(test)) {
      this.wait();
    }
    assertTrue(results.get(test));
  }
}
 

/**
 * Test case that reduces replication of a file with a lot of blocks
 * and then fails over right after those blocks enter the DN invalidation
 * queues on the active. Ensures that fencing is correct and no replicas
 * are lost.
 */
@Test
public void testNNClearsCommandsOnFailoverWithReplChanges()
    throws Exception {
  // Make lots of blocks to increase chances of triggering a bug.
  DFSTestUtil.createFile(fs, TEST_FILE_PATH, 30*SMALL_BLOCK, (short)1, 1L);

  banner("rolling NN1's edit log, forcing catch-up");
  HATestUtil.waitForStandbyToCatchUp(nn1, nn2);
  
  // Get some new replicas reported so that NN2 now considers
  // them over-replicated and schedules some more deletions
  nn1.getRpcServer().setReplication(TEST_FILE, (short) 2);
  while (BlockManagerTestUtil.getComputedDatanodeWork(
      nn1.getNamesystem().getBlockManager()) > 0) {
    LOG.info("Getting more replication work computed");
  }
  BlockManager bm1 = nn1.getNamesystem().getBlockManager();
  while (bm1.getPendingReplicationBlocksCount() > 0) {
    BlockManagerTestUtil.updateState(bm1);
    cluster.triggerHeartbeats();
    Thread.sleep(1000);
  }
  
  banner("triggering BRs");
  cluster.triggerBlockReports();
  
  nn1.getRpcServer().setReplication(TEST_FILE, (short) 1);

  
  banner("computing invalidation on nn1");

  BlockManagerTestUtil.computeInvalidationWork(
      nn1.getNamesystem().getBlockManager());
  doMetasave(nn1);

  banner("computing invalidation on nn2");
  BlockManagerTestUtil.computeInvalidationWork(
      nn2.getNamesystem().getBlockManager());
  doMetasave(nn2);

  // Dump some info for debugging purposes.
  banner("Metadata immediately before failover");
  doMetasave(nn2);


  // Transition nn2 to active even though nn1 still thinks it's active
  banner("Failing to NN2 but let NN1 continue to think it's active");
  NameNodeAdapter.abortEditLogs(nn1);
  NameNodeAdapter.enterSafeMode(nn1, false);

  
  BlockManagerTestUtil.computeInvalidationWork(
      nn2.getNamesystem().getBlockManager());
  cluster.transitionToActive(1);

  // Check that the standby picked up the replication change.
  assertEquals(1,
      nn2.getRpcServer().getFileInfo(TEST_FILE).getReplication());

  // Dump some info for debugging purposes.
  banner("Metadata immediately after failover");
  doMetasave(nn2);
  
  banner("Triggering heartbeats and block reports so that fencing is completed");
  cluster.triggerHeartbeats();
  cluster.triggerBlockReports();
  
  banner("Metadata after nodes have all block-reported");
  doMetasave(nn2);
  
  // Force a rescan of postponedMisreplicatedBlocks.
  BlockManager nn2BM = nn2.getNamesystem().getBlockManager();
  BlockManagerTestUtil.checkHeartbeat(nn2BM);
  BlockManagerTestUtil.rescanPostponedMisreplicatedBlocks(nn2BM);

  // The block should no longer be postponed.
  assertEquals(0, nn2.getNamesystem().getPostponedMisreplicatedBlocks());
  
  // Wait for NN2 to enact its deletions (replication monitor has to run, etc)
  BlockManagerTestUtil.computeInvalidationWork(
      nn2.getNamesystem().getBlockManager());

  HATestUtil.waitForNNToIssueDeletions(nn2);
  cluster.triggerHeartbeats();
  HATestUtil.waitForDNDeletions(cluster);
  cluster.triggerDeletionReports();
  assertEquals(0, nn2.getNamesystem().getUnderReplicatedBlocks());
  assertEquals(0, nn2.getNamesystem().getPendingReplicationBlocks());
  
  banner("Making sure the file is still readable");
  FileSystem fs2 = cluster.getFileSystem(1);
  DFSTestUtil.readFile(fs2, TEST_FILE_PATH);
}
 

/**
 * Test that the delegation token secret manager only runs when the
 * NN is out of safe mode. This is because the secret manager
 * has to log to the edit log, which should not be written in
 * safe mode. Regression test for HDFS-2579.
 */
@Test
public void testDTManagerInSafeMode() throws Exception {
  cluster.startDataNodes(config, 1, true, StartupOption.REGULAR, null);
  FileSystem fs = cluster.getFileSystem();
  for (int i = 0; i < 5; i++) {
    DFSTestUtil.createFile(fs, new Path("/test-" + i), 100, (short)1, 1L);
  }
  cluster.getConfiguration(0).setInt(
      DFSConfigKeys.DFS_NAMENODE_DELEGATION_KEY_UPDATE_INTERVAL_KEY, 500); 
  cluster.getConfiguration(0).setInt(
      DFSConfigKeys.DFS_NAMENODE_SAFEMODE_EXTENSION_KEY, 30000);
  cluster.setWaitSafeMode(false);
  cluster.restartNameNode();
  NameNode nn = cluster.getNameNode();
  assertTrue(nn.isInSafeMode());
  DelegationTokenSecretManager sm =
    NameNodeAdapter.getDtSecretManager(nn.getNamesystem());
  assertFalse("Secret manager should not run in safe mode", sm.isRunning());
  
  NameNodeAdapter.leaveSafeMode(nn);
  assertTrue("Secret manager should start when safe mode is exited",
      sm.isRunning());
  
  LOG.info("========= entering safemode again");
  
  NameNodeAdapter.enterSafeMode(nn, false);
  assertFalse("Secret manager should stop again when safe mode " +
      "is manually entered", sm.isRunning());
  
  // Set the cluster to leave safemode quickly on its own.
  cluster.getConfiguration(0).setInt(
      DFSConfigKeys.DFS_NAMENODE_SAFEMODE_EXTENSION_KEY, 0);
  cluster.setWaitSafeMode(true);
  cluster.restartNameNode();
  nn = cluster.getNameNode();
  sm = NameNodeAdapter.getDtSecretManager(nn.getNamesystem());

  assertFalse(nn.isInSafeMode());
  assertTrue(sm.isRunning());
}