/**
* 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.DataInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InterruptedIOException;
import java.io.RandomAccessFile;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Date;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.Random;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hdfs.protocol.FSConstants;
import org.apache.hadoop.hdfs.server.common.HdfsConstants;
import org.apache.hadoop.hdfs.server.common.InconsistentFSStateException;
import org.apache.hadoop.hdfs.server.common.Storage;
import org.apache.hadoop.hdfs.server.common.StorageInfo;
import org.apache.hadoop.hdfs.server.common.UpgradeManager;
import org.apache.hadoop.hdfs.server.common.HdfsConstants.NodeType;
import org.apache.hadoop.hdfs.server.common.HdfsConstants.StartupOption;
import org.apache.hadoop.hdfs.server.namenode.EditLogFileInputStream;
import org.apache.hadoop.hdfs.util.DataTransferThrottler;
import org.apache.hadoop.hdfs.util.InjectionEvent;
import org.apache.hadoop.hdfs.util.InjectionHandler;
import org.apache.hadoop.io.MD5Hash;
/**
* FSImage handles checkpointing and logging of the namespace edits.
*
*/
public class FSImage extends Storage {
private static final SimpleDateFormat DATE_FORM =
new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
static final String MESSAGE_DIGEST_PROPERTY = "imageMD5Digest";
private final SaveNamespaceContext saveNamespaceContext
= new SaveNamespaceContext();
//
// The filenames used for storing the images
//
enum NameNodeFile {
IMAGE ("fsimage"),
TIME ("fstime"),
EDITS ("edits"),
IMAGE_NEW ("fsimage.ckpt"),
EDITS_NEW ("edits.new");
private String fileName = null;
private NameNodeFile(String name) {this.fileName = name;}
String getName() {return fileName;}
}
// checkpoint states
enum CheckpointStates {
START(0),
ROLLED_EDITS(1),
UPLOAD_START(2),
UPLOAD_DONE(3);
private final int code;
CheckpointStates(int code) {
this.code = code;
}
public int serialize() {
return this.code;
}
public static CheckpointStates deserialize(int code) {
switch(code) {
case 0:
return CheckpointStates.START;
case 1:
return CheckpointStates.ROLLED_EDITS;
case 2:
return CheckpointStates.UPLOAD_START;
case 3:
return CheckpointStates.UPLOAD_DONE;
default: // illegal
return null;
}
}
}
/**
* Implementation of StorageDirType specific to namenode storage
* A Storage directory could be of type IMAGE which stores only fsimage,
* or of type EDITS which stores edits or of type IMAGE_AND_EDITS which
* stores both fsimage and edits.
*/
static enum NameNodeDirType implements StorageDirType {
UNDEFINED,
IMAGE,
EDITS,
IMAGE_AND_EDITS;
public StorageDirType getStorageDirType() {
return this;
}
public boolean isOfType(StorageDirType type) {
if ((this == IMAGE_AND_EDITS) && (type == IMAGE || type == EDITS))
return true;
return this == type;
}
}
protected FSNamesystem namesystem = null;
protected long checkpointTime = -1L;
FSEditLog editLog = null;
private boolean isUpgradeFinalized = false;
MD5Hash imageDigest = new MD5Hash();
private boolean newImageDigest = true;
MD5Hash checkpointImageDigest = null;
/**
* flag that controls if we try to restore failed storages
*/
private boolean restoreFailedStorage = false;
public void setRestoreFailedStorage(boolean val) {
LOG.info("enabled failed storage replicas restore");
restoreFailedStorage=val;
}
public boolean getRestoreFailedStorage() {
return restoreFailedStorage;
}
/**
* list of failed (and thus removed) storages
*/
protected List<StorageDirectory> removedStorageDirs = new ArrayList<StorageDirectory>();
/**
* Directories for importing an image from a checkpoint.
*/
private Collection<File> checkpointDirs;
private Collection<File> checkpointEditsDirs;
DataTransferThrottler imageTransferThrottler = null; // throttle image transfer
/**
* Can fs-image be rolled?
*/
volatile CheckpointStates ckptState = FSImage.CheckpointStates.START;
/**
*/
FSImage() {
this((FSNamesystem)null);
}
FSImage(FSNamesystem ns) {
super(NodeType.NAME_NODE);
this.editLog = new FSEditLog(this);
setFSNamesystem(ns);
}
/**
* Constructor
* @param conf Configuration
*/
FSImage(Configuration conf) throws IOException {
this();
setCheckpointDirectories(FSImage.getCheckpointDirs(conf, null),
FSImage.getCheckpointEditsDirs(conf, null));
long transferBandwidth = conf.getLong(
HdfsConstants.DFS_IMAGE_TRANSFER_RATE_KEY,
HdfsConstants.DFS_IMAGE_TRANSFER_RATE_DEFAULT);
if (transferBandwidth > 0) {
this.imageTransferThrottler = new DataTransferThrottler(transferBandwidth);
}
}
/**
*/
FSImage(Collection<File> fsDirs, Collection<File> fsEditsDirs)
throws IOException {
this();
setStorageDirectories(fsDirs, fsEditsDirs);
}
public FSImage(StorageInfo storageInfo) {
super(NodeType.NAME_NODE, storageInfo);
}
/**
* Represents an Image (image and edit file).
*/
public FSImage(File imageDir) throws IOException {
this();
ArrayList<File> dirs = new ArrayList<File>(1);
ArrayList<File> editsDirs = new ArrayList<File>(1);
dirs.add(imageDir);
editsDirs.add(imageDir);
setStorageDirectories(dirs, editsDirs);
}
public boolean failOnTxIdMismatch() {
if (namesystem == null) {
return true;
} else {
return namesystem.failOnTxIdMismatch();
}
}
protected FSNamesystem getFSNamesystem() {
return namesystem;
}
protected void setFSNamesystem(FSNamesystem ns) {
namesystem = ns;
}
void setStorageDirectories(Collection<File> fsNameDirs,
Collection<File> fsEditsDirs
) throws IOException {
this.storageDirs = new ArrayList<StorageDirectory>();
this.removedStorageDirs = new ArrayList<StorageDirectory>();
// Add all name dirs with appropriate NameNodeDirType
for (File dirName : fsNameDirs) {
boolean isAlsoEdits = false;
for (File editsDirName : fsEditsDirs) {
if (editsDirName.compareTo(dirName) == 0) {
isAlsoEdits = true;
fsEditsDirs.remove(editsDirName);
break;
}
}
NameNodeDirType dirType = (isAlsoEdits) ?
NameNodeDirType.IMAGE_AND_EDITS :
NameNodeDirType.IMAGE;
this.addStorageDir(new StorageDirectory(dirName, dirType));
}
// Add edits dirs if they are different from name dirs
for (File dirName : fsEditsDirs) {
this.addStorageDir(new StorageDirectory(dirName,
NameNodeDirType.EDITS));
}
}
void setCheckpointDirectories(Collection<File> dirs,
Collection<File> editsDirs) {
checkpointDirs = dirs;
checkpointEditsDirs = editsDirs;
}
static File getImageFile(StorageDirectory sd, NameNodeFile type) {
return new File(sd.getCurrentDir(), type.getName());
}
List<StorageDirectory> getRemovedStorageDirs() {
return this.removedStorageDirs;
}
File getEditFile(StorageDirectory sd) {
return getImageFile(sd, NameNodeFile.EDITS);
}
File getEditNewFile(StorageDirectory sd) {
return getImageFile(sd, NameNodeFile.EDITS_NEW);
}
File[] getFileNames(NameNodeFile type, NameNodeDirType dirType) {
ArrayList<File> list = new ArrayList<File>();
Iterator<StorageDirectory> it = (dirType == null) ? dirIterator() :
dirIterator(dirType);
for ( ;it.hasNext(); ) {
list.add(getImageFile(it.next(), type));
}
return list.toArray(new File[list.size()]);
}
File[] getImageFiles() {
return getFileNames(NameNodeFile.IMAGE, NameNodeDirType.IMAGE);
}
File[] getEditsFiles() {
return getFileNames(NameNodeFile.EDITS, NameNodeDirType.EDITS);
}
File[] getEditsNewFiles() {
return getFileNames(NameNodeFile.EDITS_NEW, NameNodeDirType.EDITS);
}
File[] getTimeFiles() {
return getFileNames(NameNodeFile.TIME, null);
}
/**
* Get the MD5 digest of the current image
* @return the MD5 digest of the current image
*/
MD5Hash getImageDigest() {
return imageDigest;
}
void setImageDigest(MD5Hash imageDigest) {
newImageDigest = false;
this.imageDigest.set(imageDigest);
}
/**
* Analyze storage directories.
* Recover from previous transitions if required.
* Perform fs state transition if necessary depending on the namespace info.
* Read storage info.
*
* @param dataDirs
* @param startOpt startup option
* @throws IOException
* @return true if the image needs to be saved or false otherwise
*/
boolean recoverTransitionRead(Collection<File> dataDirs,
Collection<File> editsDirs,
StartupOption startOpt
) throws IOException {
assert startOpt != StartupOption.FORMAT :
"NameNode formatting should be performed before reading the image";
// none of the data dirs exist
if (dataDirs.size() == 0 || editsDirs.size() == 0)
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. "
+ "\"fs.checkpoint.dir\" is not set." );
if(startOpt == StartupOption.IMPORT
&& (checkpointEditsDirs == null || checkpointEditsDirs.isEmpty()))
throw new IOException("Cannot import image from a checkpoint. "
+ "\"fs.checkpoint.edits.dir\" is not set." );
setStorageDirectories(dataDirs, editsDirs);
// 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 = false;
for (Iterator<StorageDirectory> it =
dirIterator(); it.hasNext();) {
StorageDirectory sd = it.next();
StorageState curState;
try {
curState = sd.analyzeStorage(startOpt);
// 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) {
sd.read(); // read and verify consistency with other directories
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);
}
if (!isFormatted && startOpt != StartupOption.ROLLBACK
&& startOpt != StartupOption.IMPORT)
throw new IOException("NameNode is not formatted.");
if (layoutVersion < LAST_PRE_UPGRADE_LAYOUT_VERSION) {
checkVersionUpgradable(layoutVersion);
}
if (startOpt != StartupOption.UPGRADE
&& layoutVersion < LAST_PRE_UPGRADE_LAYOUT_VERSION
&& layoutVersion != FSConstants.LAYOUT_VERSION)
throw new IOException(
"\nFile system image contains an old layout version " + layoutVersion
+ ".\nAn upgrade to version " + FSConstants.LAYOUT_VERSION
+ " is required.\nPlease restart NameNode with -upgrade option.");
// check whether distributed upgrade is reguired and/or should be continued
verifyDistributedUpgradeProgress(startOpt);
// 2. Format unformatted dirs.
this.checkpointTime = 0L;
for (Iterator<StorageDirectory> it =
dirIterator(); it.hasNext();) {
StorageDirectory sd = it.next();
StorageState curState = dataDirStates.get(sd);
switch(curState) {
case NON_EXISTENT:
assert false : 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 true;
case ROLLBACK:
doRollback();
break;
case REGULAR:
// just load the image
}
if (inUpgradeStatus()) {
namesystem.setUpgradeStartTime(FSNamesystem.now());
}
return loadFSImage();
}
/**
* @return true if Nn is under upgrade.
*/
private boolean inUpgradeStatus() {
for (Iterator <StorageDirectory> it = dirIterator(); it.hasNext();) {
StorageDirectory sd = it.next();
File preDir = sd.getPreviousDir();
if (preDir.exists()) {
return true;
}
}
return false;
}
private void doUpgrade() throws IOException {
namesystem.setUpgradeStartTime(FSNamesystem.now());
if(getDistributedUpgradeState()) {
// only distributed upgrade need to continue
// don't do version upgrade
this.loadFSImage();
initializeDistributedUpgrade();
return;
}
// Upgrade is allowed only if there are
// no previous fs states in any of the directories
for (Iterator<StorageDirectory> it =
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 = this.getCTime();
this.cTime = FSNamesystem.now(); // generate new cTime for the state
int oldLV = this.getLayoutVersion();
this.layoutVersion = FSConstants.LAYOUT_VERSION;
this.checkpointTime = FSNamesystem.now();
List<Thread> savers = new ArrayList<Thread>();
saveNamespaceContext.set(namesystem, editLog.getLastWrittenTxId());
for (Iterator<StorageDirectory> it =
dirIterator(); it.hasNext();) {
StorageDirectory sd = it.next();
LOG.info("Upgrading image directory " + sd.getRoot()
+ ".\n old LV = " + oldLV
+ "; old CTime = " + oldCTime
+ ".\n new LV = " + this.getLayoutVersion()
+ "; new CTime = " + this.getCTime());
File curDir = sd.getCurrentDir();
File prevDir = sd.getPreviousDir();
File tmpDir = sd.getPreviousTmp();
try {
assert curDir.exists() : "Current directory must exist.";
assert !prevDir.exists() : "prvious directory must not exist.";
assert !tmpDir.exists() : "prvious.tmp directory must not exist.";
// rename current to tmp
rename(curDir, tmpDir);
// save new image
if (!curDir.mkdir())
throw new IOException("Cannot create directory " + curDir);
} catch (Exception e) {
LOG.error("Error upgrading " + sd.getRoot(), e);
saveNamespaceContext.reportErrorOnStorageDirectory(sd);
continue;
}
}
for (Iterator<StorageDirectory> it = dirIterator(NameNodeDirType.IMAGE);
it.hasNext();) {
StorageDirectory sd = it.next();
// save image to image directory
FSImageSaver saver = new FSImageSaver(saveNamespaceContext, sd, false, NameNodeFile.IMAGE);
Thread saverThread = new Thread(saver, saver.toString());
savers.add(saverThread);
saverThread.start();
}
// wait until all images are saved
for (Thread saver : savers) {
try {
saver.join();
} catch (InterruptedException iex) {
LOG.info("Caught exception while waiting for thread " +
saver.getName() + " to finish. Retrying join");
throw (IOException)new InterruptedIOException().initCause(iex);
}
}
for (Iterator<StorageDirectory> it = dirIterator(NameNodeDirType.EDITS);
it.hasNext();) {
// create empty edit log file
StorageDirectory sd = it.next();
editLog.createEditLogFile(getImageFile(sd, NameNodeFile.EDITS));
}
for (Iterator<StorageDirectory> it = dirIterator(); it.hasNext();) {
StorageDirectory sd = it.next();
if (saveNamespaceContext.getErrorSDs().contains(sd)) continue;
try {
// write version and time files
sd.write();
// rename tmp to previous
rename(sd.getPreviousTmp(), sd.getPreviousDir());
} catch (IOException ioe) {
LOG.error("Error upgrading " + sd.getRoot(), ioe);
saveNamespaceContext.reportErrorOnStorageDirectory(sd);
continue;
}
isUpgradeFinalized = false;
LOG.info("Upgrade of " + sd.getRoot() + " is complete.");
}
saveNamespaceContext.clear();
processIOError(saveNamespaceContext.getErrorSDs());
initializeDistributedUpgrade();
editLog.open();
saveNamespaceContext.clear();
}
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(getFSNamesystem());
prevState.layoutVersion = FSConstants.LAYOUT_VERSION;
for (Iterator<StorageDirectory> it =
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.");
sd.read(); // read and verify consistency with other directories
continue;
}
StorageDirectory sdPrev = prevState.new StorageDirectory(sd.getRoot());
sdPrev.read(sdPrev.getPreviousVersionFile()); // read and verify consistency of the prev dir
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 =
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.getLayoutVersion()
+ "; new CTime = " + prevState.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.";
rename(curDir, tmpDir);
// rename previous to current
rename(prevDir, curDir);
// delete tmp dir
deleteDir(tmpDir);
LOG.info("Rollback of " + sd.getRoot()+ " is complete.");
}
isUpgradeFinalized = true;
// check whether name-node can start in regular mode
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() + "."
+ (getLayoutVersion()==0 ? "" :
"\n cur LV = " + this.getLayoutVersion()
+ "; cur CTime = " + this.getCTime()));
assert sd.getCurrentDir().exists() : "Current directory must exist.";
final File tmpDir = sd.getFinalizedTmp();
// rename previous to tmp and remove
rename(prevDir, tmpDir);
deleteDir(tmpDir);
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(fsNamesys);
// 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(checkpointDirs, checkpointEditsDirs,
StartupOption.REGULAR);
} finally {
ckptImage.close();
}
// return back the real image
realImage.setStorageInfo(ckptImage);
fsNamesys.dir.fsImage = realImage;
// and save it
saveNamespace(false);
}
void finalizeUpgrade() throws IOException {
for (Iterator<StorageDirectory> it =
dirIterator(); it.hasNext();) {
doFinalize(it.next());
}
isUpgradeFinalized = true;
namesystem.setUpgradeStartTime(0);
}
boolean isUpgradeFinalized() {
return isUpgradeFinalized;
}
protected void getFields(Properties props,
StorageDirectory sd
) throws IOException {
super.getFields(props, sd);
if (layoutVersion == 0)
throw new IOException("NameNode directory "
+ sd.getRoot() + " is not formatted.");
String sDUS, sDUV;
sDUS = props.getProperty("distributedUpgradeState");
sDUV = props.getProperty("distributedUpgradeVersion");
setDistributedUpgradeState(
sDUS == null? false : Boolean.parseBoolean(sDUS),
sDUV == null? getLayoutVersion() : Integer.parseInt(sDUV));
String sMd5 = props.getProperty(MESSAGE_DIGEST_PROPERTY);
if (layoutVersion <= -26) {
if (sMd5 == null) {
throw new InconsistentFSStateException(sd.getRoot(),
"file " + STORAGE_FILE_VERSION + " does not have MD5 image digest.");
}
this.setImageDigest(new MD5Hash(sMd5));
} else if (sMd5 != null) {
throw new InconsistentFSStateException(sd.getRoot(),
"file " + STORAGE_FILE_VERSION +
" has image MD5 digest when version is " + layoutVersion);
}
this.checkpointTime = readCheckpointTime(sd);
}
long readCheckpointTime(StorageDirectory sd) throws IOException {
File timeFile = getImageFile(sd, NameNodeFile.TIME);
long timeStamp = 0L;
if (timeFile.exists() && timeFile.canRead()) {
DataInputStream in = new DataInputStream(new FileInputStream(timeFile));
try {
timeStamp = in.readLong();
} finally {
in.close();
}
}
return timeStamp;
}
/**
* Write last checkpoint time and version file into the storage directory.
*
* The version file should always be written last.
* Missing or corrupted version file indicates that
* the checkpoint is not valid.
*
* @param sd storage directory
* @throws IOException
*/
protected void setFields(Properties props,
StorageDirectory sd
) throws IOException {
super.setFields(props, sd);
boolean uState = getDistributedUpgradeState();
int uVersion = getDistributedUpgradeVersion();
if(uState && uVersion != getLayoutVersion()) {
props.setProperty("distributedUpgradeState", Boolean.toString(uState));
props.setProperty("distributedUpgradeVersion", Integer.toString(uVersion));
}
if (this.newImageDigest) {
this.setImageDigest(MD5Hash.digest(
new FileInputStream(getImageFile(sd, NameNodeFile.IMAGE))));
}
props.setProperty(MESSAGE_DIGEST_PROPERTY,
this.getImageDigest().toString());
writeCheckpointTime(sd);
}
/**
* Write last checkpoint time into a separate file.
*
* @param sd
* @throws IOException
*/
void writeCheckpointTime(StorageDirectory sd) throws IOException {
if (checkpointTime < 0L)
return; // do not write negative time
File timeFile = getImageFile(sd, NameNodeFile.TIME);
if (timeFile.exists()) { timeFile.delete(); }
DataOutputStream out = new DataOutputStream(
new FileOutputStream(timeFile));
try {
out.writeLong(checkpointTime);
} finally {
out.close();
}
}
/**
* Record new checkpoint time in order to
* distinguish healthy directories from the removed ones.
* If there is an error writing new checkpoint time, the corresponding
* storage directory is removed from the list.
*/
void incrementCheckpointTime() {
this.checkpointTime++;
// Write new checkpoint time in all storage directories
for(Iterator<StorageDirectory> it =
dirIterator(); it.hasNext();) {
StorageDirectory sd = it.next();
try {
writeCheckpointTime(sd);
} catch(IOException e) {
// Close any edits stream associated with this dir and remove directory
LOG.warn("incrementCheckpointTime failed on " + sd.getRoot().getPath() + ";type="+sd.getStorageDirType());
if (sd.getStorageDirType().isOfType(NameNodeDirType.EDITS))
editLog.processIOError(sd);
//add storage to the removed list
removedStorageDirs.add(sd);
it.remove();
}
}
}
/**
* Remove storage directory given directory
*/
void processIOError(File dirName) {
for (Iterator<StorageDirectory> it =
dirIterator(); it.hasNext();) {
StorageDirectory sd = it.next();
if (sd.getRoot().getPath().equals(dirName.getPath())) {
//add storage to the removed list
LOG.warn("FSImage:processIOError: removing storage: " + dirName.getPath());
try {
sd.unlock(); //try to unlock before removing (in case it is restored)
} catch (Exception e) {
LOG.info("Unable to unlock bad storage directory : " + dirName.getPath());
}
removedStorageDirs.add(sd);
it.remove();
}
}
}
/**
* @param sds - array of SDs to process
*/
void processIOError(List<StorageDirectory> sds) throws IOException {
synchronized (sds) {
for (StorageDirectory sd : sds) {
for (Iterator<StorageDirectory> it = dirIterator(); it.hasNext();) {
StorageDirectory sd1 = it.next();
if (sd.equals(sd1)) {
// add storage to the removed list
LOG.warn("FSImage:processIOError: removing storage: "
+ sd.getRoot().getPath());
try {
sd1.unlock(); // unlock before removing (in case it will be
// restored)
} catch (Exception e) {
LOG.info("Unable to unlock bad storage directory : " + sd.getRoot().getPath());
}
removedStorageDirs.add(sd1);
it.remove();
break;
}
}
}
}
if (this.getNumStorageDirs() == 0)
throw new IOException("No more storage directory left");
}
public FSEditLog getEditLog() {
return editLog;
}
public boolean isConversionNeeded(StorageDirectory sd) throws IOException {
File oldImageDir = new File(sd.getRoot(), "image");
if (!oldImageDir.exists()) {
if(sd.getVersionFile().exists())
throw new InconsistentFSStateException(sd.getRoot(),
oldImageDir + " does not exist.");
return false;
}
// check the layout version inside the image file
File oldF = new File(oldImageDir, "fsimage");
RandomAccessFile oldFile = new RandomAccessFile(oldF, "rws");
try {
oldFile.seek(0);
int odlVersion = oldFile.readInt();
if (odlVersion < LAST_PRE_UPGRADE_LAYOUT_VERSION)
return false;
} finally {
oldFile.close();
}
return true;
}
//
// Atomic move sequence, to recover from interrupted checkpoint
//
boolean recoverInterruptedCheckpoint(StorageDirectory nameSD,
StorageDirectory editsSD)
throws IOException {
boolean needToSave = false;
File curFile = getImageFile(nameSD, NameNodeFile.IMAGE);
File ckptFile = getImageFile(nameSD, NameNodeFile.IMAGE_NEW);
//
// If we were in the midst of a checkpoint
//
if (ckptFile.exists()) {
needToSave = true;
if (getImageFile(editsSD, NameNodeFile.EDITS_NEW).exists()) {
//
// checkpointing migth have uploaded a new
// merged image, but we discard it here because we are
// not sure whether the entire merged image was uploaded
// before the namenode crashed.
//
if (!ckptFile.delete()) {
throw new IOException("Unable to delete " + ckptFile);
}
} else {
//
// checkpointing was in progress when the namenode
// shutdown. The fsimage.ckpt was created and the edits.new
// file was moved to edits. We complete that checkpoint by
// moving fsimage.new to fsimage. There is no need to
// update the fstime file here. renameTo fails on Windows
// if the destination file already exists.
//
if (!ckptFile.renameTo(curFile)) {
if (!curFile.delete())
LOG.warn("Unable to delete dir " + curFile + " before rename");
if (!ckptFile.renameTo(curFile)) {
throw new IOException("Unable to rename " + ckptFile +
" to " + curFile);
}
}
}
}
return needToSave;
}
/**
* Choose latest image from one of the directories,
* load it and merge with the edits from that directory.
*
* @return whether the image should be saved
* @throws IOException
*/
boolean loadFSImage() throws IOException {
// Now check all curFiles and see which is the newest
long latestNameCheckpointTime = Long.MIN_VALUE;
long latestEditsCheckpointTime = Long.MIN_VALUE;
StorageDirectory latestNameSD = null;
StorageDirectory latestEditsSD = null;
boolean needToSave = false;
isUpgradeFinalized = true;
Collection<String> imageDirs = new ArrayList<String>();
Collection<String> editsDirs = new ArrayList<String>();
for (Iterator<StorageDirectory> it = dirIterator(); it.hasNext();) {
StorageDirectory sd = it.next();
if (!sd.getVersionFile().exists()) {
needToSave |= true;
continue; // some of them might have just been formatted
}
boolean imageExists = false, editsExists = false;
if (sd.getStorageDirType().isOfType(NameNodeDirType.IMAGE)) {
imageExists = getImageFile(sd, NameNodeFile.IMAGE).exists();
imageDirs.add(sd.getRoot().getCanonicalPath());
}
if (sd.getStorageDirType().isOfType(NameNodeDirType.EDITS)) {
editsExists = getImageFile(sd, NameNodeFile.EDITS).exists();
editsDirs.add(sd.getRoot().getCanonicalPath());
needToSave |= getImageFile(sd, NameNodeFile.EDITS_NEW).exists();
}
checkpointTime = readCheckpointTime(sd);
if ((checkpointTime != latestNameCheckpointTime &&
latestNameCheckpointTime != Long.MIN_VALUE) ||
(checkpointTime != latestEditsCheckpointTime &&
latestEditsCheckpointTime != Long.MIN_VALUE)) {
// Force saving of new image if checkpoint time
// is not same in all of the storage directories.
needToSave |= true;
}
if (sd.getStorageDirType().isOfType(NameNodeDirType.IMAGE) &&
(latestNameCheckpointTime < checkpointTime) && imageExists) {
latestNameCheckpointTime = checkpointTime;
latestNameSD = sd;
}
if (sd.getStorageDirType().isOfType(NameNodeDirType.EDITS) &&
(latestEditsCheckpointTime < checkpointTime) && editsExists) {
latestEditsCheckpointTime = checkpointTime;
latestEditsSD = sd;
}
if (checkpointTime <= 0L)
needToSave |= true;
// set finalized flag
isUpgradeFinalized = isUpgradeFinalized && !sd.getPreviousDir().exists();
}
// We should have at least one image and one edits dirs
if (latestNameSD == null)
throw new IOException("Image file is not found in " + imageDirs);
if (latestEditsSD == null)
throw new IOException("Edits file is not found in " + editsDirs);
// Make sure we are loading image and edits from same checkpoint
if (latestNameCheckpointTime > latestEditsCheckpointTime
&& latestNameSD != latestEditsSD
&& latestNameSD.getStorageDirType() == NameNodeDirType.IMAGE
&& latestEditsSD.getStorageDirType() == NameNodeDirType.EDITS) {
// This is a rare failure when NN has image-only and edits-only
// storage directories, and fails right after saving images,
// in some of the storage directories, but before purging edits.
// See -NOTE- in saveNamespace().
LOG.error("This is a rare failure scenario!!!");
LOG.error("Image checkpoint time " + latestNameCheckpointTime
+ " > edits checkpoint time " + latestEditsCheckpointTime);
LOG.error("Name-node will treat the image as the latest state of "
+ "the namespace. Old edits will be discarded.");
} else if (latestNameCheckpointTime != latestEditsCheckpointTime)
throw new IOException("Inconsistent storage detected, "
+ "image and edits checkpoint times do not match. "
+ "image checkpoint time = " + latestNameCheckpointTime
+ "edits checkpoint time = " + latestEditsCheckpointTime);
// Recover from previous interrrupted checkpoint if any
needToSave |= recoverInterruptedCheckpoint(latestNameSD, latestEditsSD);
//
// Load in bits
//
latestNameSD.read();
//triggers re-save if image version is older
needToSave |= loadFSImage(getImageFile(latestNameSD, NameNodeFile.IMAGE));
if (latestNameCheckpointTime > latestEditsCheckpointTime) {
// the image is already current, discard edits
needToSave |= true;
}
else {
// latestNameCheckpointTime == latestEditsCheckpointTime
if(loadFSEdits(latestEditsSD) > 0) {
// trigger to save the image only if the edit log is bigger than
// fs.checkpoint.size or last checkpoint was done longer than
// fs.checkpoint.period
boolean checkpointTimeTrigger =
latestNameCheckpointTime
+ namesystem.getConf().getLong("fs.checkpoint.period", 3600) * 1000
< FSNamesystem.now();
boolean checkpointSizeTrigger =
getEditFile(latestEditsSD).length()
> namesystem.getConf().getLong("fs.checkpoint.size", 4194304);
needToSave |= (checkpointTimeTrigger || checkpointSizeTrigger);
}
}
return needToSave;
}
boolean loadFSImage(File curFile) throws IOException {
assert curFile != null : "curFile is null";
FSImageFormat.Loader loader = new FSImageFormat.Loader(namesystem.getConf(), namesystem, this);
loader.load(curFile, null);
editLog.setStartTransactionId(loader.getLoadedImageTxId() + 1);
MD5Hash readImageMd5 = loader.getLoadedImageMd5();
if (this.newImageDigest) {
this.setImageDigest(readImageMd5); // set this fsimage's checksum
} else if (!this.getImageDigest().equals(readImageMd5)) {
throw new IOException("Image file " + curFile + " is corrupt!");
}
return loader.getNeedToSave();
}
/**
* Load in the filesystem imagefrom file. It's a big list of
* filenames and blocks. Return whether we should
* "re-save" and consolidate the edit-logs
*/
boolean loadFSImage(File curFile, DataInputStream dis) throws IOException {
assert curFile != null : "curFile is null";
FSImageFormat.Loader loader = new FSImageFormat.Loader(namesystem.getConf(), namesystem, this);
loader.load(curFile, dis);
return loader.getNeedToSave();
}
/**
* Return string representing the parent of the given path.
*/
String getParent(String path) {
return path.substring(0, path.lastIndexOf(Path.SEPARATOR));
}
byte[][] getParent(byte[][] path) {
byte[][] result = new byte[path.length - 1][];
for (int i = 0; i < result.length; i++) {
result[i] = new byte[path[i].length];
System.arraycopy(path[i], 0, result[i], 0, path[i].length);
}
return result;
}
/**
* Load and merge edits from two edits files
*
* @param sd storage directory
* @return number of edits loaded
* @throws IOException
*/
int loadFSEdits(StorageDirectory sd) throws IOException {
int numEdits = 0;
EditLogFileInputStream edits =
new EditLogFileInputStream(getImageFile(sd, NameNodeFile.EDITS));
FSEditLogLoader loader = new FSEditLogLoader(namesystem);
numEdits += loader.loadFSEdits(edits, editLog.getCurrentTxId());
edits.close();
File editsNew = getImageFile(sd, NameNodeFile.EDITS_NEW);
if (editsNew.exists() && editsNew.length() > 0) {
edits = new EditLogFileInputStream(editsNew);
numEdits += loader.loadFSEdits(edits, loader.getCurrentTxId());
edits.close();
}
editLog.setStartTransactionId(loader.getCurrentTxId());
// update the counts.
getFSNamesystem().dir.updateCountForINodeWithQuota();
return numEdits;
}
// for snapshot
void saveFSImage(String dest, DataOutputStream fstream) throws IOException {
saveNamespaceContext.set(namesystem, editLog.getLastWrittenTxId());
FSImageFormat.Saver saver = new FSImageFormat.Saver(saveNamespaceContext);
FSImageCompression compression = FSImageCompression.createCompression(namesystem.getConf(), false);
saver.save(new File(dest), compression, fstream);
}
private class FSImageSaver implements Runnable {
private SaveNamespaceContext context;
private StorageDirectory sd;
private File imageFile;
private boolean forceUncompressed;
FSImageSaver(SaveNamespaceContext ctx, StorageDirectory sd, boolean forceUncompressed) {
this(ctx, sd, forceUncompressed, NameNodeFile.IMAGE_NEW);
}
FSImageSaver(SaveNamespaceContext ctx, StorageDirectory sd, boolean forceUncompressed, NameNodeFile type) {
this.context = ctx;
this.sd = sd;
this.imageFile = getImageFile(sd, type);
this.forceUncompressed = forceUncompressed;
}
public String toString() {
return "FSImage saver for " + imageFile.getAbsolutePath();
}
public void run() {
try {
InjectionHandler
.processEvent(InjectionEvent.FSIMAGE_STARTING_SAVER_THREAD);
saveCurrent(context, sd, forceUncompressed);
} catch (SaveNamespaceCancelledException ex) {
LOG.warn("FSImageSaver: - cancelling operation");
} catch (IOException ex) {
LOG.error("Unable to write image to " + imageFile.getAbsolutePath());
context.reportErrorOnStorageDirectory(sd);
}
}
}
/**
* Save the contents of the FS image
* and create empty edits.
*/
public void saveNamespace(boolean renewCheckpointTime) throws IOException {
saveNamespace(false, renewCheckpointTime);
}
/**
* Save the contents of the FS image
* and create empty edits.
* If forceUncompressed, the image will be saved uncompressed regardless of
* the fsimage compression configuration.
*/
public void saveNamespace(boolean forUncompressed, boolean renewCheckpointTime)
throws IOException {
InjectionHandler
.processEvent(InjectionEvent.FSIMAGE_STARTING_SAVE_NAMESPACE);
try {
// try to restore all failed edit logs here
assert editLog != null : "editLog must be initialized";
attemptRestoreRemovedStorage();
saveNamespaceContext.set(namesystem, editLog.getLastWrittenTxId());
InjectionHandler
.processEvent(InjectionEvent.FSIMAGE_STARTING_SAVE_NAMESPACE);
editLog.close(); // close all open streams before truncating
if (renewCheckpointTime)
this.checkpointTime = FSNamesystem.now();
// mv current -> lastcheckpoint.tmp
for (Iterator<StorageDirectory> it = dirIterator(); it.hasNext();) {
StorageDirectory sd = it.next();
try {
moveCurrent(sd);
} catch (IOException ex) {
LOG.error("Unable to move current for " + sd.getRoot(), ex);
processIOError(sd.getRoot());
}
}
// for testing only - we will wait until interruption comes
InjectionHandler
.processEvent(InjectionEvent.FSIMAGE_CREATING_SAVER_THREADS);
// Save image into current using parallel threads for saving
List<Thread> savers = new ArrayList<Thread>();
for (Iterator<StorageDirectory> it = dirIterator(NameNodeDirType.IMAGE);
it.hasNext();) {
StorageDirectory sd = it.next();
FSImageSaver saver = new FSImageSaver(saveNamespaceContext, sd, forUncompressed);
Thread saverThread = new Thread(saver, saver.toString());
savers.add(saverThread);
saverThread.start();
}
waitForThreads(savers);
savers.clear();
if (saveNamespaceContext.isCancelled()) {
processIOError(saveNamespaceContext.getErrorSDs());
deleteCancelledCheckpoint();
if (!editLog.isOpen()) editLog.open();
saveNamespaceContext.checkCancelled();
}
// -NOTE-
// If NN has image-only and edits-only storage directories and fails here
// the image will have the latest namespace state.
// During startup the image-only directories will recover by discarding
// lastcheckpoint.tmp, while
// the edits-only directories will recover by falling back
// to the old state contained in their lastcheckpoint.tmp.
// The edits directories should be discarded during startup because their
// checkpointTime is older than that of image directories.
// recreate edits in current
InjectionHandler.processEvent(InjectionEvent.FSIMAGE_SN_CLEANUP);
for (Iterator<StorageDirectory> it = dirIterator(NameNodeDirType.EDITS);
it.hasNext();) {
StorageDirectory sd = it.next();
try {
saveCurrent(saveNamespaceContext, sd, forUncompressed);
} catch (IOException ex) {
LOG.error("Unable to save edits for " + sd.getRoot(), ex);
processIOError(sd.getRoot());
}
}
// mv lastcheckpoint.tmp -> previous.checkpoint
for (Iterator<StorageDirectory> it = dirIterator(); it.hasNext();) {
StorageDirectory sd = it.next();
try {
moveLastCheckpoint(sd);
} catch (IOException ex) {
LOG.error("Unable to move last checkpoint for " + sd.getRoot(), ex);
processIOError(sd.getRoot());
}
}
if (!editLog.isOpen()) editLog.open();
processIOError(saveNamespaceContext.getErrorSDs());
ckptState = CheckpointStates.UPLOAD_DONE;
} finally {
saveNamespaceContext.clear();
}
}
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 current image and empty journal into {@code current} directory.
*/
protected void saveCurrent(SaveNamespaceContext ctx, StorageDirectory sd, boolean forceUncompressed)
throws IOException {
File curDir = sd.getCurrentDir();
LOG.info("Saving image to: " + sd.getRoot().getAbsolutePath());
NameNodeDirType dirType = (NameNodeDirType) sd.getStorageDirType();
// save new image or new edits
if (!curDir.exists() && !curDir.mkdir())
throw new IOException("Cannot create directory " + curDir);
if (dirType.isOfType(NameNodeDirType.IMAGE)) {
FSImageFormat.Saver saver = new FSImageFormat.Saver(ctx);
FSImageCompression compression = FSImageCompression.createCompression(namesystem.getConf(), forceUncompressed);
saver.save(getImageFile(sd, NameNodeFile.IMAGE), compression);
this.setImageDigest(saver.getSavedDigest());
}
if (dirType.isOfType(NameNodeDirType.EDITS))
editLog.createEditLogFile(getImageFile(sd, NameNodeFile.EDITS));
// write version and time files
sd.write();
}
/*
* Move {@code current} to {@code lastcheckpoint.tmp} and recreate empty
* {@code current}. {@code current} is moved only if it is well formatted,
* that is contains VERSION file.
*
* @see org.apache.hadoop.hdfs.server.common.Storage.StorageDirectory#
* getLastCheckpointTmp()
*
* @see org.apache.hadoop.hdfs.server.common.Storage.StorageDirectory#
* getPreviousCheckpoint()
*/
protected void moveCurrent(StorageDirectory sd) throws IOException {
File curDir = sd.getCurrentDir();
File tmpCkptDir = sd.getLastCheckpointTmp();
// mv current -> lastcheckpoint.tmp
// only if current is formatted - has VERSION file
if (sd.getVersionFile().exists()) {
assert curDir.exists() : curDir + " directory must exist.";
assert !tmpCkptDir.exists() : tmpCkptDir + " directory must not exist.";
rename(curDir, tmpCkptDir);
}
// recreate current
if (!curDir.exists() && !curDir.mkdir())
throw new IOException("Cannot create directory " + curDir);
}
/**
* Move {@code lastcheckpoint.tmp} to {@code previous.checkpoint}
*
* @see org.apache.hadoop.hdfs.server.common.Storage.StorageDirectory#
* getPreviousCheckpoint()
* @see org.apache.hadoop.hdfs.server.common.Storage.StorageDirectory#
* getLastCheckpointTmp()
*/
protected void moveLastCheckpoint(StorageDirectory sd) throws IOException {
File tmpCkptDir = sd.getLastCheckpointTmp();
File prevCkptDir = sd.getPreviousCheckpoint();
// remove previous.checkpoint
if (prevCkptDir.exists())
deleteDir(prevCkptDir);
// rename lastcheckpoint.tmp -> previous.checkpoint
if (tmpCkptDir.exists())
rename(tmpCkptDir, prevCkptDir);
}
/**
* Generate new namespaceID.
*
* namespaceID is a persistent attribute of the namespace.
* It is generated when the namenode is formatted and remains the same
* during the life cycle of the namenode.
* When a datanodes register they receive it as the registrationID,
* which is checked every time the datanode is communicating with the
* namenode. Datanodes that do not 'know' the namespaceID are rejected.
*
* @return new namespaceID
*/
private int newNamespaceID() {
Random r = new Random();
r.setSeed(FSNamesystem.now());
int newID = 0;
while(newID == 0)
newID = r.nextInt(0x7FFFFFFF); // use 31 bits only
return newID;
}
/** Create new dfs name directory. Caution: this destroys all files
* in this filesystem. */
void format(StorageDirectory sd) throws IOException {
saveNamespaceContext.set(namesystem, -1);
sd.clearDirectory(); // create currrent dir
sd.lock();
try {
saveCurrent(saveNamespaceContext, sd, false);
} finally {
sd.unlock();
}
LOG.info("Storage directory " + sd.getRoot()
+ " has been successfully formatted.");
}
public void format() throws IOException {
this.layoutVersion = FSConstants.LAYOUT_VERSION;
this.namespaceID = newNamespaceID();
this.cTime = 0L;
this.checkpointTime = FSNamesystem.now();
for (Iterator<StorageDirectory> it =
dirIterator(); it.hasNext();) {
StorageDirectory sd = it.next();
format(sd);
}
}
/**
* Moves fsimage.ckpt to fsImage and edits.new to edits
* Reopens the new edits file.
*
* @param newImageSignature the signature of the new image
*/
void rollFSImage(CheckpointSignature newImageSignature) throws IOException {
MD5Hash newImageDigest = newImageSignature.getImageDigest();
if (!newImageDigest.equals(checkpointImageDigest)) {
throw new IOException(
"Checkpoint image is corrupt: expecting an MD5 checksum of" +
newImageDigest + " but is " + checkpointImageDigest);
}
rollFSImage(newImageSignature.getImageDigest());
}
private void rollFSImage(MD5Hash newImageDigest) throws IOException {
if (ckptState != CheckpointStates.UPLOAD_DONE) {
throw new IOException("Cannot roll fsImage before rolling edits log.");
}
//
// First, verify that edits.new and fsimage.ckpt exists in all
// checkpoint directories.
//
if (!editLog.existsNew()) {
throw new IOException("New Edits file does not exist");
}
for (Iterator<StorageDirectory> it =
dirIterator(NameNodeDirType.IMAGE); it.hasNext();) {
StorageDirectory sd = it.next();
File ckpt = getImageFile(sd, NameNodeFile.IMAGE_NEW);
if (!ckpt.exists()) {
throw new IOException("Checkpoint file " + ckpt +
" does not exist");
}
}
editLog.purgeEditLog(); // renamed edits.new to edits
LOG.debug("rollFSImage after purgeEditLog: storageList=" + listStorageDirectories());
//
// Renames new image
//
for (Iterator<StorageDirectory> it =
dirIterator(NameNodeDirType.IMAGE); it.hasNext();) {
StorageDirectory sd = it.next();
File ckpt = getImageFile(sd, NameNodeFile.IMAGE_NEW);
File curFile = getImageFile(sd, NameNodeFile.IMAGE);
// renameTo fails on Windows if the destination file
// already exists.
LOG.debug("renaming " + ckpt.getAbsolutePath() + " to " + curFile.getAbsolutePath());
if (!ckpt.renameTo(curFile)) {
curFile.delete();
if (!ckpt.renameTo(curFile)) {
LOG.warn("renaming " + ckpt.getAbsolutePath() + " to " +
curFile.getAbsolutePath() + " FAILED");
// Close edit stream, if this directory is also used for edits
if (sd.getStorageDirType().isOfType(NameNodeDirType.EDITS))
editLog.processIOError(sd);
// add storage to the removed list
removedStorageDirs.add(sd);
it.remove();
}
}
}
//
// Updates the fstime file on all directories (fsimage and edits)
// and write version file
//
this.layoutVersion = FSConstants.LAYOUT_VERSION;
this.checkpointTime = FSNamesystem.now();
this.setImageDigest(newImageDigest);
for (Iterator<StorageDirectory> it =
dirIterator(); it.hasNext();) {
StorageDirectory sd = it.next();
// delete old edits if sd is the image only the directory
if (!sd.getStorageDirType().isOfType(NameNodeDirType.EDITS)) {
File editsFile = getImageFile(sd, NameNodeFile.EDITS);
editsFile.delete();
}
// delete old fsimage if sd is the edits only the directory
if (!sd.getStorageDirType().isOfType(NameNodeDirType.IMAGE)) {
File imageFile = getImageFile(sd, NameNodeFile.IMAGE);
imageFile.delete();
}
try {
sd.write();
} catch (IOException e) {
LOG.error("Cannot write file " + sd.getRoot(), e);
// Close edit stream, if this directory is also used for edits
if (sd.getStorageDirType().isOfType(NameNodeDirType.EDITS))
editLog.processIOError(sd);
//add storage to the removed list
removedStorageDirs.add(sd);
it.remove();
}
}
ckptState = FSImage.CheckpointStates.START;
}
/**
* Deletes the checkpoint file in every storage directory,
* since the checkpoint was cancelled. Moves lastcheckpoint.tmp -> current
*/
private void deleteCancelledCheckpoint() throws IOException {
ArrayList<StorageDirectory> errorDirs = new ArrayList<StorageDirectory>();
for (Iterator<StorageDirectory> it = dirIterator(); it.hasNext();) {
StorageDirectory sd = it.next();
deleteCancelledChecpointDir(sd, errorDirs);
}
processIOError(errorDirs);
}
/**
* Deletes the checkpoint file in given storage directory.
* Moves lastcheckpoint.tmp -> current
*/
private void deleteCancelledChecpointDir(StorageDirectory sd,
Collection<StorageDirectory> errorDirs) throws IOException {
LOG.info("Reverting checkpoint for : " + sd.getCurrentDir());
try {
File tmpCkptDir = sd.getLastCheckpointTmp();
File curDir = sd.getCurrentDir();
if (!tmpCkptDir.exists()) {
LOG.warn("Reverting checkpoint - lastcheckpoint.tmp "
+ "does not exist for storage directory: " + sd);
errorDirs.add(sd);
return;
}
// remove current
if (curDir.exists())
deleteDir(curDir);
// rename lastcheckpoint.tmp -> current
rename(tmpCkptDir, curDir);
} catch (IOException e) {
LOG.warn("Unable to revet checkpoint for : " + sd.getCurrentDir());
errorDirs.add(sd);
}
}
CheckpointSignature rollEditLog() throws IOException {
getEditLog().rollEditLog();
ckptState = CheckpointStates.ROLLED_EDITS;
return new CheckpointSignature(this);
}
/**
* This is called just before a new checkpoint is uploaded to the
* namenode.
*/
void validateCheckpointUpload(CheckpointSignature sig) throws IOException {
if (ckptState != CheckpointStates.ROLLED_EDITS) {
throw new IOException("Namenode is not expecting an new image " +
ckptState);
}
// verify token
long modtime = getEditLog().getFsEditTime();
if (sig.editsTime != modtime) {
throw new IOException("Namenode has an edit log with timestamp of " +
DATE_FORM.format(new Date(modtime)) +
" but new checkpoint was created using editlog " +
" with timestamp " +
DATE_FORM.format(new Date(sig.editsTime)) +
". Checkpoint Aborted.");
}
sig.validateStorageInfo(this);
ckptState = FSImage.CheckpointStates.UPLOAD_START;
}
/**
* This is called when a checkpoint upload finishes successfully.
*/
synchronized void checkpointUploadDone(MD5Hash checkpointImageMd5) {
checkpointImageDigest = checkpointImageMd5;
ckptState = CheckpointStates.UPLOAD_DONE;
}
void close() throws IOException {
getEditLog().close(true);
unlockAll();
}
/**
* Return the name of the image file.
*/
File getFsImageName() {
StorageDirectory sd = null;
for (Iterator<StorageDirectory> it =
dirIterator(NameNodeDirType.IMAGE); it.hasNext();) {
sd = it.next();
File fsImage = getImageFile(sd, NameNodeFile.IMAGE);
if (sd.getRoot().canRead() && fsImage.exists()) {
return fsImage;
}
}
return null;
}
/**
* See if any of removed storages iw "writable" again, and can be returned
* into service
*/
void attemptRestoreRemovedStorage() {
// if directory is "alive" - copy the images there...
if(!restoreFailedStorage || removedStorageDirs.size() == 0)
return; //nothing to restore
LOG.info("FSImage.attemptRestoreRemovedStorage: check removed(failed) " +
"storarge. removedStorages size = " + removedStorageDirs.size());
for(Iterator<StorageDirectory> it = this.removedStorageDirs.iterator(); it.hasNext();) {
StorageDirectory sd = it.next();
File root = sd.getRoot();
LOG.info("currently disabled dir " + root.getAbsolutePath() +
"; type="+sd.getStorageDirType() + ";canwrite="+root.canWrite());
try {
if(root.exists() && root.canWrite()) {
// when we try to restore we just need to remove all the data
// without saving current in-memory state (which could've changed).
sd.clearDirectory();
LOG.info("restoring dir " + sd.getRoot().getAbsolutePath());
this.addStorageDir(sd); // restore
it.remove();
}
} catch(IOException e) {
LOG.warn("failed to restore " + sd.getRoot().getAbsolutePath(), e);
}
}
}
public File getFsEditName() throws IOException {
return getEditLog().getFsEditName();
}
public File getFsEditNewName() throws IOException {
return getEditLog().getFsEditNewName();
}
File getFsTimeName() {
StorageDirectory sd = null;
// NameNodeFile.TIME shoul be same on all directories
for (Iterator<StorageDirectory> it =
dirIterator(); it.hasNext();)
sd = it.next();
return getImageFile(sd, NameNodeFile.TIME);
}
/**
* Return the name of the image file that is uploaded by periodic
* checkpointing.
*/
File[] getFsImageNameCheckpoint() {
ArrayList<File> list = new ArrayList<File>();
for (Iterator<StorageDirectory> it =
dirIterator(NameNodeDirType.IMAGE); it.hasNext();) {
list.add(getImageFile(it.next(), NameNodeFile.IMAGE_NEW));
}
return list.toArray(new File[list.size()]);
}
protected void corruptPreUpgradeStorage(File rootDir) throws IOException {
File oldImageDir = new File(rootDir, "image");
if (!oldImageDir.exists())
if (!oldImageDir.mkdir())
throw new IOException("Cannot create directory " + oldImageDir);
File oldImage = new File(oldImageDir, "fsimage");
if (!oldImage.exists())
// recreate old image file to let pre-upgrade versions fail
if (!oldImage.createNewFile())
throw new IOException("Cannot create file " + oldImage);
RandomAccessFile oldFile = new RandomAccessFile(oldImage, "rws");
// write new version into old image file
try {
writeCorruptedData(oldFile);
} finally {
oldFile.close();
}
}
private boolean getDistributedUpgradeState() {
FSNamesystem ns = getFSNamesystem();
return ns == null ? false : ns.getDistributedUpgradeState();
}
private int getDistributedUpgradeVersion() {
FSNamesystem ns = getFSNamesystem();
return ns == null ? 0 : ns.getDistributedUpgradeVersion();
}
private void setDistributedUpgradeState(boolean uState, int uVersion) {
getFSNamesystem().upgradeManager.setUpgradeState(uState, uVersion);
}
private void verifyDistributedUpgradeProgress(StartupOption startOpt
) throws IOException {
if(startOpt == StartupOption.ROLLBACK || startOpt == StartupOption.IMPORT)
return;
UpgradeManager um = getFSNamesystem().upgradeManager;
assert um != null : "FSNameSystem.upgradeManager is null.";
if(startOpt != StartupOption.UPGRADE) {
if(um.getUpgradeState())
throw new IOException(
"\n Previous distributed upgrade was not completed. "
+ "\n Please restart NameNode with -upgrade option.");
if(um.getDistributedUpgrades() != null)
throw new IOException("\n Distributed upgrade for NameNode version "
+ um.getUpgradeVersion() + " to current LV " + FSConstants.LAYOUT_VERSION
+ " is required.\n Please restart NameNode with -upgrade option.");
}
}
private void initializeDistributedUpgrade() throws IOException {
UpgradeManagerNamenode um = getFSNamesystem().upgradeManager;
if(! um.initializeUpgrade())
return;
// write new upgrade state into disk
writeAll();
NameNode.LOG.info("\n Distributed upgrade for NameNode version "
+ um.getUpgradeVersion() + " to current LV "
+ FSConstants.LAYOUT_VERSION + " is initialized.");
}
static Collection<File> getCheckpointDirs(Configuration conf,
String defaultName) {
Collection<String> dirNames = conf.getStringCollection("fs.checkpoint.dir");
if (dirNames.size() == 0 && defaultName != null) {
dirNames.add(defaultName);
}
Collection<File> dirs = new ArrayList<File>(dirNames.size());
for(String name : dirNames) {
dirs.add(new File(name));
}
return dirs;
}
static Collection<File> getCheckpointEditsDirs(Configuration conf,
String defaultName) {
Collection<String> dirNames = conf
.getStringCollection("fs.checkpoint.edits.dir");
if (dirNames.size() == 0 && defaultName != null) {
dirNames.add(defaultName);
}
Collection<File> dirs = new ArrayList<File>(dirNames.size());
for (String name : dirNames) {
dirs.add(new File(name));
}
return dirs;
}
public void cancelSaveNamespace(String reason) {
saveNamespaceContext.cancel(reason);
InjectionHandler.processEvent(InjectionEvent.FSIMAGE_CANCEL_REQUEST_RECEIVED);
}
}