/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.hadoop.hdfs.server.namenode;
import static org.apache.hadoop.hdfs.server.common.Util.fileAsURI;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;
import static org.mockito.Matchers.anyObject;
import static org.mockito.Mockito.doAnswer;
import static org.mockito.Mockito.doThrow;
import static org.mockito.Mockito.spy;
import java.io.File;
import java.io.IOException;
import java.io.OutputStream;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.commons.logging.impl.Log4JLogger;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.permission.FsAction;
import org.apache.hadoop.fs.permission.FsPermission;
import org.apache.hadoop.fs.permission.PermissionStatus;
import org.apache.hadoop.hdfs.DFSConfigKeys;
import org.apache.hadoop.hdfs.DFSTestUtil;
import org.apache.hadoop.hdfs.DistributedFileSystem;
import org.apache.hadoop.hdfs.HdfsConfiguration;
import org.apache.hadoop.hdfs.MiniDFSCluster;
import org.apache.hadoop.hdfs.protocol.HdfsConstants.SafeModeAction;
import org.apache.hadoop.hdfs.server.common.HdfsServerConstants.NamenodeRole;
import org.apache.hadoop.hdfs.server.common.Storage.StorageDirectory;
import org.apache.hadoop.hdfs.util.Canceler;
import org.apache.hadoop.hdfs.util.MD5FileUtils;
import org.apache.hadoop.io.IOUtils;
import org.apache.hadoop.test.GenericTestUtils;
import org.apache.hadoop.test.GenericTestUtils.DelayAnswer;
import org.apache.log4j.Level;
import org.junit.Test;
import org.mockito.Mockito;
import org.mockito.invocation.InvocationOnMock;
import org.mockito.stubbing.Answer;
/**
* Test various failure scenarios during saveNamespace() operation.
* Cases covered:
* <ol>
* <li>Recover from failure while saving into the second storage directory</li>
* <li>Recover from failure while moving current into lastcheckpoint.tmp</li>
* <li>Recover from failure while moving lastcheckpoint.tmp into
* previous.checkpoint</li>
* <li>Recover from failure while rolling edits file</li>
* </ol>
*/
public class TestSaveNamespace {
static {
((Log4JLogger)FSImage.LOG).getLogger().setLevel(Level.ALL);
}
private static final Log LOG = LogFactory.getLog(TestSaveNamespace.class);
private static class FaultySaveImage implements Answer<Void> {
int count = 0;
boolean throwRTE = true;
// generate either a RuntimeException or IOException
public FaultySaveImage(boolean throwRTE) {
this.throwRTE = throwRTE;
}
@Override
public Void answer(InvocationOnMock invocation) throws Throwable {
Object[] args = invocation.getArguments();
StorageDirectory sd = (StorageDirectory)args[1];
if (count++ == 1) {
LOG.info("Injecting fault for sd: " + sd);
if (throwRTE) {
throw new RuntimeException("Injected fault: saveFSImage second time");
} else {
throw new IOException("Injected fault: saveFSImage second time");
}
}
LOG.info("Not injecting fault for sd: " + sd);
return (Void)invocation.callRealMethod();
}
}
private enum Fault {
SAVE_SECOND_FSIMAGE_RTE,
SAVE_SECOND_FSIMAGE_IOE,
SAVE_ALL_FSIMAGES,
WRITE_STORAGE_ALL,
WRITE_STORAGE_ONE
};
private void saveNamespaceWithInjectedFault(Fault fault) throws Exception {
Configuration conf = getConf();
NameNode.initMetrics(conf, NamenodeRole.NAMENODE);
DFSTestUtil.formatNameNode(conf);
FSNamesystem fsn = FSNamesystem.loadFromDisk(conf);
// Replace the FSImage with a spy
FSImage originalImage = fsn.dir.fsImage;
NNStorage storage = originalImage.getStorage();
NNStorage spyStorage = spy(storage);
originalImage.storage = spyStorage;
FSImage spyImage = spy(originalImage);
fsn.dir.fsImage = spyImage;
boolean shouldFail = false; // should we expect the save operation to fail
// inject fault
switch(fault) {
case SAVE_SECOND_FSIMAGE_RTE:
// The spy throws a RuntimeException when writing to the second directory
doAnswer(new FaultySaveImage(true)).
when(spyImage).saveFSImage(
(SaveNamespaceContext)anyObject(),
(StorageDirectory)anyObject());
shouldFail = false;
break;
case SAVE_SECOND_FSIMAGE_IOE:
// The spy throws an IOException when writing to the second directory
doAnswer(new FaultySaveImage(false)).
when(spyImage).saveFSImage(
(SaveNamespaceContext)anyObject(),
(StorageDirectory)anyObject());
shouldFail = false;
break;
case SAVE_ALL_FSIMAGES:
// The spy throws IOException in all directories
doThrow(new RuntimeException("Injected")).
when(spyImage).saveFSImage(
(SaveNamespaceContext)anyObject(),
(StorageDirectory)anyObject());
shouldFail = true;
break;
case WRITE_STORAGE_ALL:
// The spy throws an exception before writing any VERSION files
doThrow(new RuntimeException("Injected"))
.when(spyStorage).writeAll();
shouldFail = true;
break;
case WRITE_STORAGE_ONE:
// The spy throws on exception on one particular storage directory
doAnswer(new FaultySaveImage(true))
.when(spyStorage).writeProperties((StorageDirectory)anyObject());
// TODO: unfortunately this fails -- should be improved.
// See HDFS-2173.
shouldFail = true;
break;
}
try {
doAnEdit(fsn, 1);
// Save namespace - this may fail, depending on fault injected
fsn.setSafeMode(SafeModeAction.SAFEMODE_ENTER);
try {
fsn.saveNamespace();
if (shouldFail) {
fail("Did not fail!");
}
} catch (Exception e) {
if (! shouldFail) {
throw e;
} else {
LOG.info("Test caught expected exception", e);
}
}
fsn.setSafeMode(SafeModeAction.SAFEMODE_LEAVE);
// Should still be able to perform edits
doAnEdit(fsn, 2);
// Now shut down and restart the namesystem
originalImage.close();
fsn.close();
fsn = null;
// Start a new namesystem, which should be able to recover
// the namespace from the previous incarnation.
fsn = FSNamesystem.loadFromDisk(conf);
// Make sure the image loaded including our edits.
checkEditExists(fsn, 1);
checkEditExists(fsn, 2);
} finally {
if (fsn != null) {
fsn.close();
}
}
}
/**
* Verify that a saveNamespace command brings faulty directories
* in fs.name.dir and fs.edit.dir back online.
*/
@Test (timeout=30000)
public void testReinsertnamedirsInSavenamespace() throws Exception {
// create a configuration with the key to restore error
// directories in fs.name.dir
Configuration conf = getConf();
conf.setBoolean(DFSConfigKeys.DFS_NAMENODE_NAME_DIR_RESTORE_KEY, true);
NameNode.initMetrics(conf, NamenodeRole.NAMENODE);
DFSTestUtil.formatNameNode(conf);
FSNamesystem fsn = FSNamesystem.loadFromDisk(conf);
// Replace the FSImage with a spy
FSImage originalImage = fsn.dir.fsImage;
NNStorage storage = originalImage.getStorage();
FSImage spyImage = spy(originalImage);
fsn.dir.fsImage = spyImage;
FileSystem fs = FileSystem.getLocal(conf);
File rootDir = storage.getStorageDir(0).getRoot();
Path rootPath = new Path(rootDir.getPath(), "current");
final FsPermission permissionNone = new FsPermission((short) 0);
final FsPermission permissionAll = new FsPermission(
FsAction.ALL, FsAction.READ_EXECUTE, FsAction.READ_EXECUTE);
fs.setPermission(rootPath, permissionNone);
try {
doAnEdit(fsn, 1);
fsn.setSafeMode(SafeModeAction.SAFEMODE_ENTER);
// Save namespace - should mark the first storage dir as faulty
// since it's not traversable.
LOG.info("Doing the first savenamespace.");
fsn.saveNamespace();
LOG.info("First savenamespace sucessful.");
assertTrue("Savenamespace should have marked one directory as bad." +
" But found " + storage.getRemovedStorageDirs().size() +
" bad directories.",
storage.getRemovedStorageDirs().size() == 1);
fs.setPermission(rootPath, permissionAll);
// The next call to savenamespace should try inserting the
// erroneous directory back to fs.name.dir. This command should
// be successful.
LOG.info("Doing the second savenamespace.");
fsn.saveNamespace();
LOG.warn("Second savenamespace sucessful.");
assertTrue("Savenamespace should have been successful in removing " +
" bad directories from Image." +
" But found " + storage.getRemovedStorageDirs().size() +
" bad directories.",
storage.getRemovedStorageDirs().size() == 0);
// Now shut down and restart the namesystem
LOG.info("Shutting down fsimage.");
originalImage.close();
fsn.close();
fsn = null;
// Start a new namesystem, which should be able to recover
// the namespace from the previous incarnation.
LOG.info("Loading new FSmage from disk.");
fsn = FSNamesystem.loadFromDisk(conf);
// Make sure the image loaded including our edit.
LOG.info("Checking reloaded image.");
checkEditExists(fsn, 1);
LOG.info("Reloaded image is good.");
} finally {
if (rootDir.exists()) {
fs.setPermission(rootPath, permissionAll);
}
if (fsn != null) {
try {
fsn.close();
} catch (Throwable t) {
LOG.fatal("Failed to shut down", t);
}
}
}
}
@Test (timeout=30000)
public void testRTEWhileSavingSecondImage() throws Exception {
saveNamespaceWithInjectedFault(Fault.SAVE_SECOND_FSIMAGE_RTE);
}
@Test (timeout=30000)
public void testIOEWhileSavingSecondImage() throws Exception {
saveNamespaceWithInjectedFault(Fault.SAVE_SECOND_FSIMAGE_IOE);
}
@Test (timeout=30000)
public void testCrashInAllImageDirs() throws Exception {
saveNamespaceWithInjectedFault(Fault.SAVE_ALL_FSIMAGES);
}
@Test (timeout=30000)
public void testCrashWhenWritingVersionFiles() throws Exception {
saveNamespaceWithInjectedFault(Fault.WRITE_STORAGE_ALL);
}
@Test (timeout=30000)
public void testCrashWhenWritingVersionFileInOneDir() throws Exception {
saveNamespaceWithInjectedFault(Fault.WRITE_STORAGE_ONE);
}
/**
* Test case where savenamespace fails in all directories
* and then the NN shuts down. Here we should recover from the
* failed checkpoint since it only affected ".ckpt" files, not
* valid image files
*/
@Test (timeout=30000)
public void testFailedSaveNamespace() throws Exception {
doTestFailedSaveNamespace(false);
}
/**
* Test case where saveNamespace fails in all directories, but then
* the operator restores the directories and calls it again.
* This should leave the NN in a clean state for next start.
*/
@Test (timeout=30000)
public void testFailedSaveNamespaceWithRecovery() throws Exception {
doTestFailedSaveNamespace(true);
}
/**
* Injects a failure on all storage directories while saving namespace.
*
* @param restoreStorageAfterFailure if true, will try to save again after
* clearing the failure injection
*/
public void doTestFailedSaveNamespace(boolean restoreStorageAfterFailure)
throws Exception {
Configuration conf = getConf();
NameNode.initMetrics(conf, NamenodeRole.NAMENODE);
DFSTestUtil.formatNameNode(conf);
FSNamesystem fsn = FSNamesystem.loadFromDisk(conf);
// Replace the FSImage with a spy
final FSImage originalImage = fsn.dir.fsImage;
NNStorage storage = originalImage.getStorage();
storage.close(); // unlock any directories that FSNamesystem's initialization may have locked
NNStorage spyStorage = spy(storage);
originalImage.storage = spyStorage;
FSImage spyImage = spy(originalImage);
fsn.dir.fsImage = spyImage;
spyImage.storage.setStorageDirectories(
FSNamesystem.getNamespaceDirs(conf),
FSNamesystem.getNamespaceEditsDirs(conf));
doThrow(new IOException("Injected fault: saveFSImage")).
when(spyImage).saveFSImage(
(SaveNamespaceContext)anyObject(),
(StorageDirectory)anyObject());
try {
doAnEdit(fsn, 1);
// Save namespace
fsn.setSafeMode(SafeModeAction.SAFEMODE_ENTER);
try {
fsn.saveNamespace();
fail("saveNamespace did not fail even when all directories failed!");
} catch (IOException ioe) {
LOG.info("Got expected exception", ioe);
}
// Ensure that, if storage dirs come back online, things work again.
if (restoreStorageAfterFailure) {
Mockito.reset(spyImage);
spyStorage.setRestoreFailedStorage(true);
fsn.saveNamespace();
checkEditExists(fsn, 1);
}
// Now shut down and restart the NN
originalImage.close();
fsn.close();
fsn = null;
// Start a new namesystem, which should be able to recover
// the namespace from the previous incarnation.
fsn = FSNamesystem.loadFromDisk(conf);
// Make sure the image loaded including our edits.
checkEditExists(fsn, 1);
} finally {
if (fsn != null) {
fsn.close();
}
}
}
@Test (timeout=30000)
public void testSaveWhileEditsRolled() throws Exception {
Configuration conf = getConf();
NameNode.initMetrics(conf, NamenodeRole.NAMENODE);
DFSTestUtil.formatNameNode(conf);
FSNamesystem fsn = FSNamesystem.loadFromDisk(conf);
try {
doAnEdit(fsn, 1);
CheckpointSignature sig = fsn.rollEditLog();
LOG.warn("Checkpoint signature: " + sig);
// Do another edit
doAnEdit(fsn, 2);
// Save namespace
fsn.setSafeMode(SafeModeAction.SAFEMODE_ENTER);
fsn.saveNamespace();
// Now shut down and restart the NN
fsn.close();
fsn = null;
// Start a new namesystem, which should be able to recover
// the namespace from the previous incarnation.
fsn = FSNamesystem.loadFromDisk(conf);
// Make sure the image loaded including our edits.
checkEditExists(fsn, 1);
checkEditExists(fsn, 2);
} finally {
if (fsn != null) {
fsn.close();
}
}
}
@Test (timeout=30000)
public void testTxIdPersistence() throws Exception {
Configuration conf = getConf();
NameNode.initMetrics(conf, NamenodeRole.NAMENODE);
DFSTestUtil.formatNameNode(conf);
FSNamesystem fsn = FSNamesystem.loadFromDisk(conf);
try {
// We have a BEGIN_LOG_SEGMENT txn to start
assertEquals(1, fsn.getEditLog().getLastWrittenTxId());
doAnEdit(fsn, 1);
assertEquals(2, fsn.getEditLog().getLastWrittenTxId());
fsn.setSafeMode(SafeModeAction.SAFEMODE_ENTER);
fsn.saveNamespace();
// 2 more txns: END the first segment, BEGIN a new one
assertEquals(4, fsn.getEditLog().getLastWrittenTxId());
// Shut down and restart
fsn.getFSImage().close();
fsn.close();
// 1 more txn to END that segment
assertEquals(5, fsn.getEditLog().getLastWrittenTxId());
fsn = null;
fsn = FSNamesystem.loadFromDisk(conf);
// 1 more txn to start new segment on restart
assertEquals(6, fsn.getEditLog().getLastWrittenTxId());
} finally {
if (fsn != null) {
fsn.close();
}
}
}
/**
* Test for save namespace should succeed when parent directory renamed with
* open lease and destination directory exist.
* This test is a regression for HDFS-2827
*/
@Test
public void testSaveNamespaceWithRenamedLease() throws Exception {
MiniDFSCluster cluster = new MiniDFSCluster.Builder(new Configuration())
.numDataNodes(1).build();
cluster.waitActive();
DistributedFileSystem fs = (DistributedFileSystem) cluster.getFileSystem();
OutputStream out = null;
try {
fs.mkdirs(new Path("/test-target"));
out = fs.create(new Path("/test-source/foo")); // don't close
fs.rename(new Path("/test-source/"), new Path("/test-target/"));
fs.setSafeMode(SafeModeAction.SAFEMODE_ENTER);
cluster.getNameNodeRpc().saveNamespace();
fs.setSafeMode(SafeModeAction.SAFEMODE_LEAVE);
} finally {
IOUtils.cleanup(LOG, out, fs);
if (cluster != null) {
cluster.shutdown();
}
}
}
@Test(timeout=20000)
public void testCancelSaveNamespace() throws Exception {
Configuration conf = getConf();
NameNode.initMetrics(conf, NamenodeRole.NAMENODE);
DFSTestUtil.formatNameNode(conf);
FSNamesystem fsn = FSNamesystem.loadFromDisk(conf);
// Replace the FSImage with a spy
final FSImage image = fsn.dir.fsImage;
NNStorage storage = image.getStorage();
storage.close(); // unlock any directories that FSNamesystem's initialization may have locked
storage.setStorageDirectories(
FSNamesystem.getNamespaceDirs(conf),
FSNamesystem.getNamespaceEditsDirs(conf));
FSNamesystem spyFsn = spy(fsn);
final FSNamesystem finalFsn = spyFsn;
DelayAnswer delayer = new GenericTestUtils.DelayAnswer(LOG);
doAnswer(delayer).when(spyFsn).getGenerationStampV2();
ExecutorService pool = Executors.newFixedThreadPool(2);
try {
doAnEdit(fsn, 1);
final Canceler canceler = new Canceler();
// Save namespace
fsn.setSafeMode(SafeModeAction.SAFEMODE_ENTER);
try {
Future<Void> saverFuture = pool.submit(new Callable<Void>() {
@Override
public Void call() throws Exception {
image.saveNamespace(finalFsn, canceler);
return null;
}
});
// Wait until saveNamespace calls getGenerationStamp
delayer.waitForCall();
// then cancel the saveNamespace
Future<Void> cancelFuture = pool.submit(new Callable<Void>() {
@Override
public Void call() throws Exception {
canceler.cancel("cancelled");
return null;
}
});
// give the cancel call time to run
Thread.sleep(500);
// allow saveNamespace to proceed - it should check the cancel flag after
// this point and throw an exception
delayer.proceed();
cancelFuture.get();
saverFuture.get();
fail("saveNamespace did not fail even though cancelled!");
} catch (Throwable t) {
GenericTestUtils.assertExceptionContains(
"SaveNamespaceCancelledException", t);
}
LOG.info("Successfully cancelled a saveNamespace");
// Check that we have only the original image and not any
// cruft left over from half-finished images
FSImageTestUtil.logStorageContents(LOG, storage);
for (StorageDirectory sd : storage.dirIterable(null)) {
File curDir = sd.getCurrentDir();
GenericTestUtils.assertGlobEquals(curDir, "fsimage_.*",
NNStorage.getImageFileName(0),
NNStorage.getImageFileName(0) + MD5FileUtils.MD5_SUFFIX);
}
} finally {
if (fsn != null) {
fsn.close();
}
}
}
@Test (timeout=30000)
public void testSaveNamespaceWithDanglingLease() throws Exception {
MiniDFSCluster cluster = new MiniDFSCluster.Builder(new Configuration())
.numDataNodes(1).build();
cluster.waitActive();
DistributedFileSystem fs = (DistributedFileSystem) cluster.getFileSystem();
try {
cluster.getNamesystem().leaseManager.addLease("me", "/non-existent");
fs.setSafeMode(SafeModeAction.SAFEMODE_ENTER);
cluster.getNameNodeRpc().saveNamespace();
fs.setSafeMode(SafeModeAction.SAFEMODE_LEAVE);
} finally {
if (cluster != null) {
cluster.shutdown();
}
}
}
private void doAnEdit(FSNamesystem fsn, int id) throws IOException {
// Make an edit
fsn.mkdirs(
"/test" + id,
new PermissionStatus("test", "Test",
new FsPermission((short)0777)),
true);
}
private void checkEditExists(FSNamesystem fsn, int id) throws IOException {
// Make sure the image loaded including our edit.
assertNotNull(fsn.getFileInfo("/test" + id, false));
}
private Configuration getConf() throws IOException {
String baseDir = MiniDFSCluster.getBaseDirectory();
String nameDirs = fileAsURI(new File(baseDir, "name1")) + "," +
fileAsURI(new File(baseDir, "name2"));
Configuration conf = new HdfsConfiguration();
FileSystem.setDefaultUri(conf, "hdfs://localhost:0");
conf.set(DFSConfigKeys.DFS_NAMENODE_HTTP_ADDRESS_KEY, "0.0.0.0:0");
conf.set(DFSConfigKeys.DFS_NAMENODE_NAME_DIR_KEY, nameDirs);
conf.set(DFSConfigKeys.DFS_NAMENODE_EDITS_DIR_KEY, nameDirs);
conf.set(DFSConfigKeys.DFS_NAMENODE_SECONDARY_HTTP_ADDRESS_KEY, "0.0.0.0:0");
conf.setBoolean(DFSConfigKeys.DFS_PERMISSIONS_ENABLED_KEY, false);
return conf;
}
}