| /** |
| * 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 java.io.Closeable; |
| import java.io.File; |
| import java.io.IOException; |
| import java.net.URI; |
| import java.util.ArrayList; |
| import java.util.Collection; |
| import java.util.Collections; |
| import java.util.HashMap; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.Map; |
| |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.classification.InterfaceStability; |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.hadoop.hdfs.protocol.FSConstants; |
| import org.apache.hadoop.hdfs.protocol.LayoutVersion; |
| import org.apache.hadoop.hdfs.protocol.LayoutVersion.Feature; |
| import org.apache.hadoop.hdfs.server.common.InconsistentFSStateException; |
| import org.apache.hadoop.hdfs.server.common.Storage; |
| import org.apache.hadoop.hdfs.server.common.Storage.StorageDirectory; |
| import org.apache.hadoop.hdfs.server.common.Storage.StorageState; |
| import org.apache.hadoop.hdfs.server.common.Util; |
| import static org.apache.hadoop.hdfs.server.common.Util.now; |
| import org.apache.hadoop.hdfs.server.common.HdfsConstants.NamenodeRole; |
| import org.apache.hadoop.hdfs.server.common.HdfsConstants.StartupOption; |
| import org.apache.hadoop.hdfs.server.namenode.FSImageStorageInspector.LoadPlan; |
| import org.apache.hadoop.hdfs.server.namenode.NNStorage.NameNodeDirType; |
| import org.apache.hadoop.hdfs.server.namenode.NNStorage.NameNodeFile; |
| import org.apache.hadoop.hdfs.server.protocol.CheckpointCommand; |
| import org.apache.hadoop.hdfs.server.protocol.NamenodeCommand; |
| import org.apache.hadoop.hdfs.server.protocol.NamenodeProtocol; |
| import org.apache.hadoop.hdfs.server.protocol.NamenodeRegistration; |
| import org.apache.hadoop.hdfs.util.MD5FileUtils; |
| import org.apache.hadoop.io.MD5Hash; |
| import org.apache.hadoop.hdfs.DFSConfigKeys; |
| |
| import com.google.common.base.Joiner; |
| import com.google.common.base.Preconditions; |
| import com.google.common.collect.Lists; |
| |
| /** |
| * FSImage handles checkpointing and logging of the namespace edits. |
| * |
| */ |
| @InterfaceAudience.Private |
| @InterfaceStability.Evolving |
| public class FSImage implements Closeable { |
| protected static final Log LOG = LogFactory.getLog(FSImage.class.getName()); |
| |
| protected FSNamesystem namesystem = null; |
| protected FSEditLog editLog = null; |
| private boolean isUpgradeFinalized = false; |
| |
| protected NNStorage storage; |
| |
| /** |
| * The last transaction ID that was either loaded from an image |
| * or loaded by loading edits files. |
| */ |
| protected long lastAppliedTxId = 0; |
| |
| /** |
| * URIs for importing an image from a checkpoint. In the default case, |
| * URIs will represent directories. |
| */ |
| private Collection<URI> checkpointDirs; |
| private Collection<URI> checkpointEditsDirs; |
| |
| final private Configuration conf; |
| |
| private final NNStorageRetentionManager archivalManager; |
| |
| /** |
| * Construct an FSImage. |
| * @param conf Configuration |
| * @see #FSImage(Configuration conf, FSNamesystem ns, |
| * Collection imageDirs, Collection editsDirs) |
| * @throws IOException if default directories are invalid. |
| */ |
| public FSImage(Configuration conf) throws IOException { |
| this(conf, (FSNamesystem)null); |
| } |
| |
| /** |
| * Construct an FSImage |
| * @param conf Configuration |
| * @param ns The FSNamesystem using this image. |
| * @see #FSImage(Configuration conf, FSNamesystem ns, |
| * Collection imageDirs, Collection editsDirs) |
| * @throws IOException if default directories are invalid. |
| */ |
| private FSImage(Configuration conf, FSNamesystem ns) throws IOException { |
| this(conf, ns, |
| FSNamesystem.getNamespaceDirs(conf), |
| FSNamesystem.getNamespaceEditsDirs(conf)); |
| } |
| |
| /** |
| * Construct the FSImage. Set the default checkpoint directories. |
| * |
| * Setup storage and initialize the edit log. |
| * |
| * @param conf Configuration |
| * @param ns The FSNamesystem using this image. |
| * @param imageDirs Directories the image can be stored in. |
| * @param editsDirs Directories the editlog can be stored in. |
| * @throws IOException if directories are invalid. |
| */ |
| protected FSImage(Configuration conf, FSNamesystem ns, |
| Collection<URI> imageDirs, Collection<URI> editsDirs) |
| throws IOException { |
| this.conf = conf; |
| setCheckpointDirectories(FSImage.getCheckpointDirs(conf, null), |
| FSImage.getCheckpointEditsDirs(conf, null)); |
| |
| storage = new NNStorage(conf, imageDirs, editsDirs); |
| if (ns != null) { |
| storage.setUpgradeManager(ns.upgradeManager); |
| } |
| |
| if(conf.getBoolean(DFSConfigKeys.DFS_NAMENODE_NAME_DIR_RESTORE_KEY, |
| DFSConfigKeys.DFS_NAMENODE_NAME_DIR_RESTORE_DEFAULT)) { |
| storage.setRestoreFailedStorage(true); |
| } |
| |
| this.editLog = new FSEditLog(storage); |
| setFSNamesystem(ns); |
| |
| archivalManager = new NNStorageRetentionManager(conf, storage, editLog); |
| } |
| |
| protected FSNamesystem getFSNamesystem() { |
| return namesystem; |
| } |
| |
| void setFSNamesystem(FSNamesystem ns) { |
| namesystem = ns; |
| if (ns != null) { |
| storage.setUpgradeManager(ns.upgradeManager); |
| } |
| } |
| |
| void setCheckpointDirectories(Collection<URI> dirs, |
| Collection<URI> editsDirs) { |
| checkpointDirs = dirs; |
| checkpointEditsDirs = editsDirs; |
| } |
| |
| void format(String clusterId) throws IOException { |
| storage.format(clusterId); |
| saveFSImageInAllDirs(0); |
| } |
| |
| /** |
| * Analyze storage directories. |
| * Recover from previous transitions if required. |
| * Perform fs state transition if necessary depending on the namespace info. |
| * Read storage info. |
| * |
| * @throws IOException |
| * @return true if the image needs to be saved or false otherwise |
| */ |
| boolean recoverTransitionRead(StartupOption startOpt) |
| throws IOException { |
| assert startOpt != StartupOption.FORMAT : |
| "NameNode formatting should be performed before reading the image"; |
| |
| Collection<URI> imageDirs = storage.getImageDirectories(); |
| Collection<URI> editsDirs = storage.getEditsDirectories(); |
| |
| // none of the data dirs exist |
| if((imageDirs.size() == 0 || editsDirs.size() == 0) |
| && startOpt != StartupOption.IMPORT) |
| throw new IOException( |
| "All specified directories are not accessible or do not exist."); |
| |
| if(startOpt == StartupOption.IMPORT |
| && (checkpointDirs == null || checkpointDirs.isEmpty())) |
| throw new IOException("Cannot import image from a checkpoint. " |
| + "\"dfs.namenode.checkpoint.dir\" is not set." ); |
| |
| if(startOpt == StartupOption.IMPORT |
| && (checkpointEditsDirs == null || checkpointEditsDirs.isEmpty())) |
| throw new IOException("Cannot import image from a checkpoint. " |
| + "\"dfs.namenode.checkpoint.dir\" is not set." ); |
| |
| // 1. For each data directory calculate its state and |
| // check whether all is consistent before transitioning. |
| Map<StorageDirectory, StorageState> dataDirStates = |
| new HashMap<StorageDirectory, StorageState>(); |
| boolean isFormatted = recoverStorageDirs(startOpt, dataDirStates); |
| |
| if (LOG.isTraceEnabled()) { |
| LOG.trace("Data dir states:\n " + |
| Joiner.on("\n ").withKeyValueSeparator(": ") |
| .join(dataDirStates)); |
| } |
| |
| if (!isFormatted && startOpt != StartupOption.ROLLBACK |
| && startOpt != StartupOption.IMPORT) { |
| throw new IOException("NameNode is not formatted."); |
| } |
| |
| |
| int layoutVersion = storage.getLayoutVersion(); |
| if (layoutVersion < Storage.LAST_PRE_UPGRADE_LAYOUT_VERSION) { |
| NNStorage.checkVersionUpgradable(storage.getLayoutVersion()); |
| } |
| if (startOpt != StartupOption.UPGRADE |
| && layoutVersion < Storage.LAST_PRE_UPGRADE_LAYOUT_VERSION |
| && layoutVersion != FSConstants.LAYOUT_VERSION) { |
| throw new IOException( |
| "\nFile system image contains an old layout version " |
| + storage.getLayoutVersion() + ".\nAn upgrade to version " |
| + FSConstants.LAYOUT_VERSION + " is required.\n" |
| + "Please restart NameNode with -upgrade option."); |
| } |
| |
| storage.processStartupOptionsForUpgrade(startOpt, layoutVersion); |
| |
| // check whether distributed upgrade is required and/or should be continued |
| storage.verifyDistributedUpgradeProgress(startOpt); |
| |
| // 2. Format unformatted dirs. |
| for (Iterator<StorageDirectory> it = storage.dirIterator(); it.hasNext();) { |
| StorageDirectory sd = it.next(); |
| StorageState curState = dataDirStates.get(sd); |
| switch(curState) { |
| case NON_EXISTENT: |
| throw new IOException(StorageState.NON_EXISTENT + |
| " state cannot be here"); |
| case NOT_FORMATTED: |
| LOG.info("Storage directory " + sd.getRoot() + " is not formatted."); |
| LOG.info("Formatting ..."); |
| sd.clearDirectory(); // create empty currrent dir |
| break; |
| default: |
| break; |
| } |
| } |
| |
| // 3. Do transitions |
| switch(startOpt) { |
| case UPGRADE: |
| doUpgrade(); |
| return false; // upgrade saved image already |
| case IMPORT: |
| doImportCheckpoint(); |
| return false; // import checkpoint saved image already |
| case ROLLBACK: |
| doRollback(); |
| break; |
| case REGULAR: |
| // just load the image |
| } |
| |
| return loadFSImage(); |
| } |
| |
| /** |
| * For each storage directory, performs recovery of incomplete transitions |
| * (eg. upgrade, rollback, checkpoint) and inserts the directory's storage |
| * state into the dataDirStates map. |
| * @param dataDirStates output of storage directory states |
| * @return true if there is at least one valid formatted storage directory |
| */ |
| private boolean recoverStorageDirs(StartupOption startOpt, |
| Map<StorageDirectory, StorageState> dataDirStates) throws IOException { |
| boolean isFormatted = false; |
| for (Iterator<StorageDirectory> it = |
| storage.dirIterator(); it.hasNext();) { |
| StorageDirectory sd = it.next(); |
| StorageState curState; |
| try { |
| curState = sd.analyzeStorage(startOpt, storage); |
| // sd is locked but not opened |
| switch(curState) { |
| case NON_EXISTENT: |
| // name-node fails if any of the configured storage dirs are missing |
| throw new InconsistentFSStateException(sd.getRoot(), |
| "storage directory does not exist or is not accessible."); |
| case NOT_FORMATTED: |
| break; |
| case NORMAL: |
| break; |
| default: // recovery is possible |
| sd.doRecover(curState); |
| } |
| if (curState != StorageState.NOT_FORMATTED |
| && startOpt != StartupOption.ROLLBACK) { |
| // read and verify consistency with other directories |
| storage.readProperties(sd); |
| isFormatted = true; |
| } |
| if (startOpt == StartupOption.IMPORT && isFormatted) |
| // import of a checkpoint is allowed only into empty image directories |
| throw new IOException("Cannot import image from a checkpoint. " |
| + " NameNode already contains an image in " + sd.getRoot()); |
| } catch (IOException ioe) { |
| sd.unlock(); |
| throw ioe; |
| } |
| dataDirStates.put(sd,curState); |
| } |
| return isFormatted; |
| } |
| |
| private void doUpgrade() throws IOException { |
| if(storage.getDistributedUpgradeState()) { |
| // only distributed upgrade need to continue |
| // don't do version upgrade |
| this.loadFSImage(); |
| storage.initializeDistributedUpgrade(); |
| return; |
| } |
| // Upgrade is allowed only if there are |
| // no previous fs states in any of the directories |
| for (Iterator<StorageDirectory> it = storage.dirIterator(); it.hasNext();) { |
| StorageDirectory sd = it.next(); |
| if (sd.getPreviousDir().exists()) |
| throw new InconsistentFSStateException(sd.getRoot(), |
| "previous fs state should not exist during upgrade. " |
| + "Finalize or rollback first."); |
| } |
| |
| // load the latest image |
| this.loadFSImage(); |
| |
| // Do upgrade for each directory |
| long oldCTime = storage.getCTime(); |
| storage.cTime = now(); // generate new cTime for the state |
| int oldLV = storage.getLayoutVersion(); |
| storage.layoutVersion = FSConstants.LAYOUT_VERSION; |
| |
| List<StorageDirectory> errorSDs = |
| Collections.synchronizedList(new ArrayList<StorageDirectory>()); |
| for (Iterator<StorageDirectory> it = storage.dirIterator(); it.hasNext();) { |
| StorageDirectory sd = it.next(); |
| LOG.info("Starting upgrade of image directory " + sd.getRoot() |
| + ".\n old LV = " + oldLV |
| + "; old CTime = " + oldCTime |
| + ".\n new LV = " + storage.getLayoutVersion() |
| + "; new CTime = " + storage.getCTime()); |
| try { |
| File curDir = sd.getCurrentDir(); |
| File prevDir = sd.getPreviousDir(); |
| File tmpDir = sd.getPreviousTmp(); |
| assert curDir.exists() : "Current directory must exist."; |
| assert !prevDir.exists() : "prvious directory must not exist."; |
| assert !tmpDir.exists() : "prvious.tmp directory must not exist."; |
| assert !editLog.isOpen() : "Edits log must not be open."; |
| |
| // rename current to tmp |
| NNStorage.rename(curDir, tmpDir); |
| |
| if (!curDir.mkdir()) { |
| throw new IOException("Cannot create directory " + curDir); |
| } |
| } catch (Exception e) { |
| LOG.error("Failed to move aside pre-upgrade storage " + |
| "in image directory " + sd.getRoot(), e); |
| errorSDs.add(sd); |
| continue; |
| } |
| } |
| storage.reportErrorsOnDirectories(errorSDs); |
| errorSDs.clear(); |
| |
| saveFSImageInAllDirs(editLog.getLastWrittenTxId()); |
| |
| for (Iterator<StorageDirectory> it = storage.dirIterator(); it.hasNext();) { |
| StorageDirectory sd = it.next(); |
| try { |
| // Write the version file, since saveFsImage above only makes the |
| // fsimage_<txid>, and the directory is otherwise empty. |
| storage.writeProperties(sd); |
| |
| File prevDir = sd.getPreviousDir(); |
| File tmpDir = sd.getPreviousTmp(); |
| // rename tmp to previous |
| NNStorage.rename(tmpDir, prevDir); |
| } catch (IOException ioe) { |
| LOG.error("Unable to rename temp to previous for " + sd.getRoot(), ioe); |
| errorSDs.add(sd); |
| continue; |
| } |
| LOG.info("Upgrade of " + sd.getRoot() + " is complete."); |
| } |
| storage.reportErrorsOnDirectories(errorSDs); |
| |
| isUpgradeFinalized = false; |
| if (!storage.getRemovedStorageDirs().isEmpty()) { |
| //during upgrade, it's a fatal error to fail any storage directory |
| throw new IOException("Upgrade failed in " |
| + storage.getRemovedStorageDirs().size() |
| + " storage directory(ies), previously logged."); |
| } |
| storage.initializeDistributedUpgrade(); |
| } |
| |
| private void doRollback() throws IOException { |
| // Rollback is allowed only if there is |
| // a previous fs states in at least one of the storage directories. |
| // Directories that don't have previous state do not rollback |
| boolean canRollback = false; |
| FSImage prevState = new FSImage(conf, getFSNamesystem()); |
| prevState.getStorage().layoutVersion = FSConstants.LAYOUT_VERSION; |
| for (Iterator<StorageDirectory> it = storage.dirIterator(); it.hasNext();) { |
| StorageDirectory sd = it.next(); |
| File prevDir = sd.getPreviousDir(); |
| if (!prevDir.exists()) { // use current directory then |
| LOG.info("Storage directory " + sd.getRoot() |
| + " does not contain previous fs state."); |
| // read and verify consistency with other directories |
| storage.readProperties(sd); |
| continue; |
| } |
| |
| // read and verify consistency of the prev dir |
| prevState.getStorage().readPreviousVersionProperties(sd); |
| |
| if (prevState.getLayoutVersion() != FSConstants.LAYOUT_VERSION) { |
| throw new IOException( |
| "Cannot rollback to storage version " + |
| prevState.getLayoutVersion() + |
| " using this version of the NameNode, which uses storage version " + |
| FSConstants.LAYOUT_VERSION + ". " + |
| "Please use the previous version of HDFS to perform the rollback."); |
| } |
| canRollback = true; |
| } |
| if (!canRollback) |
| throw new IOException("Cannot rollback. None of the storage " |
| + "directories contain previous fs state."); |
| |
| // Now that we know all directories are going to be consistent |
| // Do rollback for each directory containing previous state |
| for (Iterator<StorageDirectory> it = storage.dirIterator(); it.hasNext();) { |
| StorageDirectory sd = it.next(); |
| File prevDir = sd.getPreviousDir(); |
| if (!prevDir.exists()) |
| continue; |
| |
| LOG.info("Rolling back storage directory " + sd.getRoot() |
| + ".\n new LV = " + prevState.getStorage().getLayoutVersion() |
| + "; new CTime = " + prevState.getStorage().getCTime()); |
| File tmpDir = sd.getRemovedTmp(); |
| assert !tmpDir.exists() : "removed.tmp directory must not exist."; |
| // rename current to tmp |
| File curDir = sd.getCurrentDir(); |
| assert curDir.exists() : "Current directory must exist."; |
| NNStorage.rename(curDir, tmpDir); |
| // rename previous to current |
| NNStorage.rename(prevDir, curDir); |
| |
| // delete tmp dir |
| NNStorage.deleteDir(tmpDir); |
| LOG.info("Rollback of " + sd.getRoot()+ " is complete."); |
| } |
| isUpgradeFinalized = true; |
| // check whether name-node can start in regular mode |
| storage.verifyDistributedUpgradeProgress(StartupOption.REGULAR); |
| } |
| |
| private void doFinalize(StorageDirectory sd) throws IOException { |
| File prevDir = sd.getPreviousDir(); |
| if (!prevDir.exists()) { // already discarded |
| LOG.info("Directory " + prevDir + " does not exist."); |
| LOG.info("Finalize upgrade for " + sd.getRoot()+ " is not required."); |
| return; |
| } |
| LOG.info("Finalizing upgrade for storage directory " |
| + sd.getRoot() + "." |
| + (storage.getLayoutVersion()==0 ? "" : |
| "\n cur LV = " + storage.getLayoutVersion() |
| + "; cur CTime = " + storage.getCTime())); |
| assert sd.getCurrentDir().exists() : "Current directory must exist."; |
| final File tmpDir = sd.getFinalizedTmp(); |
| // rename previous to tmp and remove |
| NNStorage.rename(prevDir, tmpDir); |
| NNStorage.deleteDir(tmpDir); |
| isUpgradeFinalized = true; |
| LOG.info("Finalize upgrade for " + sd.getRoot()+ " is complete."); |
| } |
| |
| /** |
| * Load image from a checkpoint directory and save it into the current one. |
| * @throws IOException |
| */ |
| void doImportCheckpoint() throws IOException { |
| FSNamesystem fsNamesys = getFSNamesystem(); |
| FSImage ckptImage = new FSImage(conf, fsNamesys, |
| checkpointDirs, checkpointEditsDirs); |
| // replace real image with the checkpoint image |
| FSImage realImage = fsNamesys.getFSImage(); |
| assert realImage == this; |
| fsNamesys.dir.fsImage = ckptImage; |
| // load from the checkpoint dirs |
| try { |
| ckptImage.recoverTransitionRead(StartupOption.REGULAR); |
| } finally { |
| ckptImage.close(); |
| } |
| // return back the real image |
| realImage.getStorage().setStorageInfo(ckptImage.getStorage()); |
| realImage.getEditLog().setNextTxId(ckptImage.getEditLog().getLastWrittenTxId()+1); |
| |
| fsNamesys.dir.fsImage = realImage; |
| realImage.getStorage().setBlockPoolID(ckptImage.getBlockPoolID()); |
| // and save it but keep the same checkpointTime |
| saveNamespace(); |
| getStorage().writeAll(); |
| } |
| |
| void finalizeUpgrade() throws IOException { |
| for (Iterator<StorageDirectory> it = storage.dirIterator(); it.hasNext();) { |
| StorageDirectory sd = it.next(); |
| doFinalize(sd); |
| } |
| } |
| |
| boolean isUpgradeFinalized() { |
| return isUpgradeFinalized; |
| } |
| |
| public FSEditLog getEditLog() { |
| return editLog; |
| } |
| |
| void openEditLog() throws IOException { |
| assert editLog != null : "editLog must be initialized"; |
| Preconditions.checkState(!editLog.isOpen(), |
| "edit log should not yet be open"); |
| editLog.open(); |
| storage.writeTransactionIdFileToStorage(editLog.getCurSegmentTxId()); |
| }; |
| |
| /** |
| * Toss the current image and namesystem, reloading from the specified |
| * file. |
| */ |
| void reloadFromImageFile(File file) throws IOException { |
| namesystem.dir.reset(); |
| |
| LOG.debug("Reloading namespace from " + file); |
| loadFSImage(file); |
| } |
| |
| /** |
| * Choose latest image from one of the directories, |
| * load it and merge with the edits from that directory. |
| * |
| * Saving and loading fsimage should never trigger symlink resolution. |
| * The paths that are persisted do not have *intermediate* symlinks |
| * because intermediate symlinks are resolved at the time files, |
| * directories, and symlinks are created. All paths accessed while |
| * loading or saving fsimage should therefore only see symlinks as |
| * the final path component, and the functions called below do not |
| * resolve symlinks that are the final path component. |
| * |
| * @return whether the image should be saved |
| * @throws IOException |
| */ |
| boolean loadFSImage() throws IOException { |
| FSImageStorageInspector inspector = storage.readAndInspectDirs(); |
| |
| isUpgradeFinalized = inspector.isUpgradeFinalized(); |
| |
| boolean needToSave = inspector.needToSave(); |
| |
| // Plan our load. This will throw if it's impossible to load from the |
| // data that's available. |
| LoadPlan loadPlan = inspector.createLoadPlan(); |
| LOG.debug("Planning to load image using following plan:\n" + loadPlan); |
| |
| |
| // Recover from previous interrupted checkpoint, if any |
| needToSave |= loadPlan.doRecovery(); |
| |
| // |
| // Load in bits |
| // |
| StorageDirectory sdForProperties = |
| loadPlan.getStorageDirectoryForProperties(); |
| storage.readProperties(sdForProperties); |
| File imageFile = loadPlan.getImageFile(); |
| |
| try { |
| if (LayoutVersion.supports(Feature.TXID_BASED_LAYOUT, |
| getLayoutVersion())) { |
| // For txid-based layout, we should have a .md5 file |
| // next to the image file |
| loadFSImage(imageFile); |
| } else if (LayoutVersion.supports(Feature.FSIMAGE_CHECKSUM, |
| getLayoutVersion())) { |
| // In 0.22, we have the checksum stored in the VERSION file. |
| String md5 = storage.getDeprecatedProperty( |
| NNStorage.DEPRECATED_MESSAGE_DIGEST_PROPERTY); |
| if (md5 == null) { |
| throw new InconsistentFSStateException(sdForProperties.getRoot(), |
| "Message digest property " + |
| NNStorage.DEPRECATED_MESSAGE_DIGEST_PROPERTY + |
| " not set for storage directory " + sdForProperties.getRoot()); |
| } |
| loadFSImage(imageFile, new MD5Hash(md5)); |
| } else { |
| // We don't have any record of the md5sum |
| loadFSImage(imageFile, null); |
| } |
| } catch (IOException ioe) { |
| throw new IOException("Failed to load image from " + loadPlan.getImageFile(), ioe); |
| } |
| |
| long numLoaded = loadEdits(loadPlan.getEditsFiles()); |
| needToSave |= needsResaveBasedOnStaleCheckpoint(imageFile, numLoaded); |
| |
| // update the txid for the edit log |
| editLog.setNextTxId(storage.getMostRecentCheckpointTxId() + numLoaded + 1); |
| return needToSave; |
| } |
| |
| |
| /** |
| * @param imageFile the image file that was loaded |
| * @param numEditsLoaded the number of edits loaded from edits logs |
| * @return true if the NameNode should automatically save the namespace |
| * when it is started, due to the latest checkpoint being too old. |
| */ |
| private boolean needsResaveBasedOnStaleCheckpoint( |
| File imageFile, long numEditsLoaded) { |
| final long checkpointPeriod = conf.getLong( |
| DFSConfigKeys.DFS_NAMENODE_CHECKPOINT_PERIOD_KEY, |
| DFSConfigKeys.DFS_NAMENODE_CHECKPOINT_PERIOD_DEFAULT); |
| final long checkpointTxnCount = conf.getLong( |
| DFSConfigKeys.DFS_NAMENODE_CHECKPOINT_TXNS_KEY, |
| DFSConfigKeys.DFS_NAMENODE_CHECKPOINT_TXNS_DEFAULT); |
| long checkpointAge = System.currentTimeMillis() - imageFile.lastModified(); |
| |
| return (checkpointAge > checkpointPeriod * 1000) || |
| (numEditsLoaded > checkpointTxnCount); |
| } |
| |
| /** |
| * Load the specified list of edit files into the image. |
| * @return the number of transactions loaded |
| */ |
| protected long loadEdits(List<File> editLogs) throws IOException { |
| LOG.debug("About to load edits:\n " + Joiner.on("\n ").join(editLogs)); |
| |
| long startingTxId = getLastAppliedTxId() + 1; |
| |
| FSEditLogLoader loader = new FSEditLogLoader(namesystem); |
| int numLoaded = 0; |
| // Load latest edits |
| for (File edits : editLogs) { |
| LOG.debug("Reading " + edits + " expecting start txid #" + startingTxId); |
| EditLogFileInputStream editIn = new EditLogFileInputStream(edits); |
| int thisNumLoaded = loader.loadFSEdits(editIn, startingTxId); |
| startingTxId += thisNumLoaded; |
| numLoaded += thisNumLoaded; |
| lastAppliedTxId += thisNumLoaded; |
| editIn.close(); |
| } |
| |
| // update the counts |
| getFSNamesystem().dir.updateCountForINodeWithQuota(); |
| return numLoaded; |
| } |
| |
| |
| /** |
| * Load the image namespace from the given image file, verifying |
| * it against the MD5 sum stored in its associated .md5 file. |
| */ |
| private void loadFSImage(File imageFile) throws IOException { |
| MD5Hash expectedMD5 = MD5FileUtils.readStoredMd5ForFile(imageFile); |
| if (expectedMD5 == null) { |
| throw new IOException("No MD5 file found corresponding to image file " |
| + imageFile); |
| } |
| loadFSImage(imageFile, expectedMD5); |
| } |
| |
| /** |
| * Load in the filesystem image from file. It's a big list of |
| * filenames and blocks. Return whether we should |
| * "re-save" and consolidate the edit-logs |
| */ |
| private void loadFSImage(File curFile, MD5Hash expectedMd5) throws IOException { |
| FSImageFormat.Loader loader = new FSImageFormat.Loader( |
| conf, getFSNamesystem()); |
| loader.load(curFile); |
| namesystem.setBlockPoolId(this.getBlockPoolID()); |
| |
| // Check that the image digest we loaded matches up with what |
| // we expected |
| MD5Hash readImageMd5 = loader.getLoadedImageMd5(); |
| if (expectedMd5 != null && |
| !expectedMd5.equals(readImageMd5)) { |
| throw new IOException("Image file " + curFile + |
| " is corrupt with MD5 checksum of " + readImageMd5 + |
| " but expecting " + expectedMd5); |
| } |
| |
| long txId = loader.getLoadedImageTxId(); |
| LOG.info("Loaded image for txid " + txId + " from " + curFile); |
| lastAppliedTxId = txId; |
| storage.setMostRecentCheckpointTxId(txId); |
| } |
| |
| /** |
| * Save the contents of the FS image to the file. |
| */ |
| void saveFSImage(StorageDirectory sd, long txid) throws IOException { |
| File newFile = NNStorage.getStorageFile(sd, NameNodeFile.IMAGE_NEW, txid); |
| File dstFile = NNStorage.getStorageFile(sd, NameNodeFile.IMAGE, txid); |
| |
| FSImageFormat.Saver saver = new FSImageFormat.Saver(); |
| FSImageCompression compression = FSImageCompression.createCompression(conf); |
| saver.save(newFile, txid, getFSNamesystem(), compression); |
| |
| MD5FileUtils.saveMD5File(dstFile, saver.getSavedDigest()); |
| storage.setMostRecentCheckpointTxId(txid); |
| } |
| |
| /** |
| * FSImageSaver is being run in a separate thread when saving |
| * FSImage. There is one thread per each copy of the image. |
| * |
| * FSImageSaver assumes that it was launched from a thread that holds |
| * FSNamesystem lock and waits for the execution of FSImageSaver thread |
| * to finish. |
| * This way we are guraranteed that the namespace is not being updated |
| * while multiple instances of FSImageSaver are traversing it |
| * and writing it out. |
| */ |
| private class FSImageSaver implements Runnable { |
| private StorageDirectory sd; |
| private List<StorageDirectory> errorSDs; |
| private final long txid; |
| |
| FSImageSaver(StorageDirectory sd, List<StorageDirectory> errorSDs, long txid) { |
| this.sd = sd; |
| this.errorSDs = errorSDs; |
| this.txid = txid; |
| } |
| |
| public void run() { |
| try { |
| saveFSImage(sd, txid); |
| } catch (Throwable t) { |
| LOG.error("Unable to save image for " + sd.getRoot(), t); |
| errorSDs.add(sd); |
| } |
| } |
| |
| public String toString() { |
| return "FSImageSaver for " + sd.getRoot() + |
| " of type " + sd.getStorageDirType(); |
| } |
| } |
| |
| private void waitForThreads(List<Thread> threads) { |
| for (Thread thread : threads) { |
| while (thread.isAlive()) { |
| try { |
| thread.join(); |
| } catch (InterruptedException iex) { |
| LOG.error("Caught exception while waiting for thread " + |
| thread.getName() + " to finish. Retrying join"); |
| } |
| } |
| } |
| } |
| /** |
| * Save the contents of the FS image to a new image file in each of the |
| * current storage directories. |
| */ |
| void saveNamespace() throws IOException { |
| assert editLog != null : "editLog must be initialized"; |
| storage.attemptRestoreRemovedStorage(); |
| |
| boolean editLogWasOpen = editLog.isOpen(); |
| |
| if (editLogWasOpen) { |
| editLog.endCurrentLogSegment(true); |
| } |
| long imageTxId = editLog.getLastWrittenTxId(); |
| try { |
| saveFSImageInAllDirs(imageTxId); |
| storage.writeAll(); |
| } finally { |
| if (editLogWasOpen) { |
| editLog.startLogSegment(imageTxId + 1, true); |
| // Take this opportunity to note the current transaction |
| storage.writeTransactionIdFileToStorage(imageTxId + 1); |
| } |
| } |
| |
| } |
| |
| protected void saveFSImageInAllDirs(long txid) throws IOException { |
| if (storage.getNumStorageDirs(NameNodeDirType.IMAGE) == 0) { |
| throw new IOException("No image directories available!"); |
| } |
| |
| List<StorageDirectory> errorSDs = |
| Collections.synchronizedList(new ArrayList<StorageDirectory>()); |
| |
| List<Thread> saveThreads = new ArrayList<Thread>(); |
| // save images into current |
| for (Iterator<StorageDirectory> it |
| = storage.dirIterator(NameNodeDirType.IMAGE); it.hasNext();) { |
| StorageDirectory sd = it.next(); |
| FSImageSaver saver = new FSImageSaver(sd, errorSDs, txid); |
| Thread saveThread = new Thread(saver, saver.toString()); |
| saveThreads.add(saveThread); |
| saveThread.start(); |
| } |
| waitForThreads(saveThreads); |
| saveThreads.clear(); |
| storage.reportErrorsOnDirectories(errorSDs); |
| |
| if (storage.getNumStorageDirs(NameNodeDirType.IMAGE) == 0) { |
| throw new IOException( |
| "Failed to save in any storage directories while saving namespace."); |
| } |
| |
| renameCheckpoint(txid); |
| |
| // Since we now have a new checkpoint, we can clean up some |
| // old edit logs and checkpoints. |
| purgeOldStorage(); |
| } |
| |
| /** |
| * Purge any files in the storage directories that are no longer |
| * necessary. |
| */ |
| public void purgeOldStorage() { |
| try { |
| archivalManager.purgeOldStorage(); |
| } catch (Exception e) { |
| LOG.warn("Unable to purge old storage", e); |
| } |
| } |
| |
| /** |
| * Renames new image |
| */ |
| private void renameCheckpoint(long txid) throws IOException { |
| ArrayList<StorageDirectory> al = null; |
| |
| for (StorageDirectory sd : storage.dirIterable(NameNodeDirType.IMAGE)) { |
| try { |
| renameCheckpointInDir(sd, txid); |
| } catch (IOException ioe) { |
| LOG.warn("Unable to rename checkpoint in " + sd, ioe); |
| if (al == null) { |
| al = Lists.newArrayList(); |
| } |
| al.add(sd); |
| } |
| } |
| if(al != null) storage.reportErrorsOnDirectories(al); |
| } |
| |
| private void renameCheckpointInDir(StorageDirectory sd, long txid) |
| throws IOException { |
| File ckpt = NNStorage.getStorageFile(sd, NameNodeFile.IMAGE_NEW, txid); |
| File curFile = NNStorage.getStorageFile(sd, NameNodeFile.IMAGE, txid); |
| // renameTo fails on Windows if the destination file |
| // already exists. |
| if(LOG.isDebugEnabled()) { |
| LOG.debug("renaming " + ckpt.getAbsolutePath() |
| + " to " + curFile.getAbsolutePath()); |
| } |
| if (!ckpt.renameTo(curFile)) { |
| if (!curFile.delete() || !ckpt.renameTo(curFile)) { |
| throw new IOException("renaming " + ckpt.getAbsolutePath() + " to " + |
| curFile.getAbsolutePath() + " FAILED"); |
| } |
| } |
| } |
| |
| CheckpointSignature rollEditLog() throws IOException { |
| getEditLog().rollEditLog(); |
| // Record this log segment ID in all of the storage directories, so |
| // we won't miss this log segment on a restart if the edits directories |
| // go missing. |
| storage.writeTransactionIdFileToStorage(getEditLog().getCurSegmentTxId()); |
| return new CheckpointSignature(this); |
| } |
| |
| /** |
| * Start checkpoint. |
| * <p> |
| * If backup storage contains image that is newer than or incompatible with |
| * what the active name-node has, then the backup node should shutdown.<br> |
| * If the backup image is older than the active one then it should |
| * be discarded and downloaded from the active node.<br> |
| * If the images are the same then the backup image will be used as current. |
| * |
| * @param bnReg the backup node registration. |
| * @param nnReg this (active) name-node registration. |
| * @return {@link NamenodeCommand} if backup node should shutdown or |
| * {@link CheckpointCommand} prescribing what backup node should |
| * do with its image. |
| * @throws IOException |
| */ |
| NamenodeCommand startCheckpoint(NamenodeRegistration bnReg, // backup node |
| NamenodeRegistration nnReg) // active name-node |
| throws IOException { |
| String msg = null; |
| // Verify that checkpoint is allowed |
| if(bnReg.getNamespaceID() != storage.getNamespaceID()) |
| msg = "Name node " + bnReg.getAddress() |
| + " has incompatible namespace id: " + bnReg.getNamespaceID() |
| + " expected: " + storage.getNamespaceID(); |
| else if(bnReg.isRole(NamenodeRole.NAMENODE)) |
| msg = "Name node " + bnReg.getAddress() |
| + " role " + bnReg.getRole() + ": checkpoint is not allowed."; |
| else if(bnReg.getLayoutVersion() < storage.getLayoutVersion() |
| || (bnReg.getLayoutVersion() == storage.getLayoutVersion() |
| && bnReg.getCTime() > storage.getCTime())) |
| // remote node has newer image age |
| msg = "Name node " + bnReg.getAddress() |
| + " has newer image layout version: LV = " +bnReg.getLayoutVersion() |
| + " cTime = " + bnReg.getCTime() |
| + ". Current version: LV = " + storage.getLayoutVersion() |
| + " cTime = " + storage.getCTime(); |
| if(msg != null) { |
| LOG.error(msg); |
| return new NamenodeCommand(NamenodeProtocol.ACT_SHUTDOWN); |
| } |
| boolean needToReturnImg = true; |
| if(storage.getNumStorageDirs(NameNodeDirType.IMAGE) == 0) |
| // do not return image if there are no image directories |
| needToReturnImg = false; |
| CheckpointSignature sig = rollEditLog(); |
| return new CheckpointCommand(sig, needToReturnImg); |
| } |
| |
| /** |
| * End checkpoint. |
| * <p> |
| * Rename uploaded checkpoint to the new image; |
| * purge old edits file; |
| * rename edits.new to edits; |
| * redirect edit log streams to the new edits; |
| * update checkpoint time if the remote node is a checkpoint only node. |
| * |
| * @param sig |
| * @param remoteNNRole |
| * @throws IOException |
| */ |
| void endCheckpoint(CheckpointSignature sig, |
| NamenodeRole remoteNNRole) throws IOException { |
| sig.validateStorageInfo(this); |
| } |
| |
| /** |
| * This is called by the 2NN after having downloaded an image, and by |
| * the NN after having received a new image from the 2NN. It |
| * renames the image from fsimage_N.ckpt to fsimage_N and also |
| * saves the related .md5 file into place. |
| */ |
| synchronized void saveDigestAndRenameCheckpointImage( |
| long txid, MD5Hash digest) throws IOException { |
| renameCheckpoint(txid); |
| List<StorageDirectory> badSds = Lists.newArrayList(); |
| |
| for (StorageDirectory sd : storage.dirIterable(NameNodeDirType.IMAGE)) { |
| File imageFile = NNStorage.getImageFile(sd, txid); |
| try { |
| MD5FileUtils.saveMD5File(imageFile, digest); |
| } catch (IOException ioe) { |
| badSds.add(sd); |
| } |
| } |
| storage.reportErrorsOnDirectories(badSds); |
| |
| // So long as this is the newest image available, |
| // advertise it as such to other checkpointers |
| // from now on |
| if (txid > storage.getMostRecentCheckpointTxId()) { |
| storage.setMostRecentCheckpointTxId(txid); |
| } |
| } |
| |
| synchronized public void close() throws IOException { |
| if (editLog != null) { // 2NN doesn't have any edit log |
| getEditLog().close(); |
| } |
| storage.close(); |
| } |
| |
| |
| /** |
| * Retrieve checkpoint dirs from configuration. |
| * |
| * @param conf the Configuration |
| * @param defaultValue a default value for the attribute, if null |
| * @return a Collection of URIs representing the values in |
| * dfs.namenode.checkpoint.dir configuration property |
| */ |
| static Collection<URI> getCheckpointDirs(Configuration conf, |
| String defaultValue) { |
| Collection<String> dirNames = conf.getStringCollection(DFSConfigKeys.DFS_NAMENODE_CHECKPOINT_DIR_KEY); |
| if (dirNames.size() == 0 && defaultValue != null) { |
| dirNames.add(defaultValue); |
| } |
| return Util.stringCollectionAsURIs(dirNames); |
| } |
| |
| static Collection<URI> getCheckpointEditsDirs(Configuration conf, |
| String defaultName) { |
| Collection<String> dirNames = |
| conf.getStringCollection(DFSConfigKeys.DFS_NAMENODE_CHECKPOINT_EDITS_DIR_KEY); |
| if (dirNames.size() == 0 && defaultName != null) { |
| dirNames.add(defaultName); |
| } |
| return Util.stringCollectionAsURIs(dirNames); |
| } |
| |
| public NNStorage getStorage() { |
| return storage; |
| } |
| |
| public int getLayoutVersion() { |
| return storage.getLayoutVersion(); |
| } |
| |
| public int getNamespaceID() { |
| return storage.getNamespaceID(); |
| } |
| |
| public String getClusterID() { |
| return storage.getClusterID(); |
| } |
| |
| public String getBlockPoolID() { |
| return storage.getBlockPoolID(); |
| } |
| |
| public synchronized long getLastAppliedTxId() { |
| return lastAppliedTxId; |
| } |
| } |
