/**
* 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 org.apache.commons.logging.*;
import org.apache.hadoop.fs.ContentSummary;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.Trash;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.permission.*;
import org.apache.hadoop.hdfs.protocol.*;
import org.apache.hadoop.hdfs.server.common.HdfsConstants.StartupOption;
import org.apache.hadoop.hdfs.server.common.IncorrectVersionException;
import org.apache.hadoop.hdfs.server.common.UpgradeStatusReport;
import org.apache.hadoop.hdfs.server.namenode.FSNamesystem.CompleteFileStatus;
import org.apache.hadoop.hdfs.server.namenode.metrics.NameNodeMetrics;
import org.apache.hadoop.hdfs.server.protocol.BlocksWithLocations;
import org.apache.hadoop.hdfs.server.protocol.DatanodeCommand;
import org.apache.hadoop.hdfs.server.protocol.DatanodeProtocol;
import org.apache.hadoop.hdfs.server.protocol.DatanodeRegistration;
import org.apache.hadoop.hdfs.server.protocol.NamenodeProtocol;
import org.apache.hadoop.hdfs.server.protocol.NamespaceInfo;
import org.apache.hadoop.hdfs.server.protocol.UpgradeCommand;
import org.apache.hadoop.ipc.*;
import org.apache.hadoop.conf.*;
import org.apache.hadoop.util.StringUtils;
import org.apache.hadoop.net.NetUtils;
import org.apache.hadoop.net.NetworkTopology;
import org.apache.hadoop.security.UserGroupInformation;
import java.io.*;
import java.net.*;
import java.util.Collection;
import java.util.Iterator;
/**********************************************************
* NameNode serves as both directory namespace manager and
* "inode table" for the Hadoop DFS. There is a single NameNode
* running in any DFS deployment. (Well, except when there
* is a second backup/failover NameNode.)
*
* The NameNode controls two critical tables:
* 1) filename->blocksequence (namespace)
* 2) block->machinelist ("inodes")
*
* The first table is stored on disk and is very precious.
* The second table is rebuilt every time the NameNode comes
* up.
*
* 'NameNode' refers to both this class as well as the 'NameNode server'.
* The 'FSNamesystem' class actually performs most of the filesystem
* management. The majority of the 'NameNode' class itself is concerned
* with exposing the IPC interface to the outside world, plus some
* configuration management.
*
* NameNode implements the ClientProtocol interface, which allows
* clients to ask for DFS services. ClientProtocol is not
* designed for direct use by authors of DFS client code. End-users
* should instead use the org.apache.nutch.hadoop.fs.FileSystem class.
*
* NameNode also implements the DatanodeProtocol interface, used by
* DataNode programs that actually store DFS data blocks. These
* methods are invoked repeatedly and automatically by all the
* DataNodes in a DFS deployment.
*
* NameNode also implements the NamenodeProtocol interface, used by
* secondary namenodes or rebalancing processes to get partial namenode's
* state, for example partial blocksMap etc.
**********************************************************/
public class NameNode implements ClientProtocol, DatanodeProtocol,
NamenodeProtocol, FSConstants {
public long getProtocolVersion(String protocol,
long clientVersion) throws IOException {
if (protocol.equals(ClientProtocol.class.getName())) {
return ClientProtocol.versionID;
} else if (protocol.equals(DatanodeProtocol.class.getName())){
return DatanodeProtocol.versionID;
} else if (protocol.equals(NamenodeProtocol.class.getName())){
return NamenodeProtocol.versionID;
} else {
throw new IOException("Unknown protocol to name node: " + protocol);
}
}
public static final int DEFAULT_PORT = 8020;
public static final Log LOG = LogFactory.getLog(NameNode.class.getName());
public static final Log stateChangeLog = LogFactory.getLog("org.apache.hadoop.hdfs.StateChange");
public FSNamesystem namesystem;
private Server server;
private Thread emptier;
private int handlerCount = 2;
private boolean supportAppends = true; // allow appending to hdfs files
private InetSocketAddress nameNodeAddress = null;
/** only used for testing purposes */
private boolean stopRequested = false;
/** Format a new filesystem. Destroys any filesystem that may already
* exist at this location. **/
public static void format(Configuration conf) throws IOException {
format(conf, false);
}
static NameNodeMetrics myMetrics;
public static NameNodeMetrics getNameNodeMetrics() {
return myMetrics;
}
public static InetSocketAddress getAddress(String address) {
return NetUtils.createSocketAddr(address, DEFAULT_PORT);
}
public static InetSocketAddress getAddress(Configuration conf) {
return getAddress(FileSystem.getDefaultUri(conf).getAuthority());
}
public static URI getUri(InetSocketAddress namenode) {
int port = namenode.getPort();
String portString = port == DEFAULT_PORT ? "" : (":"+port);
return URI.create("hdfs://"+ namenode.getHostName()+portString);
}
/**
* Initialize the server
*
* @param address hostname:port to bind to
* @param conf the configuration
*/
private void initialize(String address, Configuration conf) throws IOException {
InetSocketAddress socAddr = NameNode.getAddress(address);
this.supportAppends = conf.getBoolean("dfs.support.append", true);
this.handlerCount = conf.getInt("dfs.namenode.handler.count", 10);
this.server = RPC.getServer(this, socAddr.getHostName(), socAddr.getPort(),
handlerCount, false, conf);
// The rpc-server port can be ephemeral... ensure we have the correct info
this.nameNodeAddress = this.server.getListenerAddress();
FileSystem.setDefaultUri(conf, getUri(nameNodeAddress));
LOG.info("Namenode up at: " + this.nameNodeAddress);
myMetrics = new NameNodeMetrics(conf, this);
this.namesystem = new FSNamesystem(this, conf);
this.server.start(); //start RPC server
this.emptier = new Thread(new Trash(conf).getEmptier(), "Trash Emptier");
this.emptier.setDaemon(true);
this.emptier.start();
}
/**
* Start NameNode.
* <p>
* The name-node can be started with one of the following startup options:
* <ul>
* <li>{@link org.apache.hadoop.hdfs.server.common.HdfsConstants.StartupOption#REGULAR REGULAR} - normal startup</li>
* <li>{@link org.apache.hadoop.hdfs.server.common.HdfsConstants.StartupOption#FORMAT FORMAT} - format name node</li>
* <li>{@link org.apache.hadoop.hdfs.server.common.HdfsConstants.StartupOption#UPGRADE UPGRADE} - start the cluster
* upgrade and create a snapshot of the current file system state</li>
* <li>{@link org.apache.hadoop.hdfs.server.common.HdfsConstants.StartupOption#ROLLBACK ROLLBACK} - roll the
* cluster back to the previous state</li>
* </ul>
* The option is passed via configuration field:
* <tt>dfs.namenode.startup</tt>
*
* The conf will be modified to reflect the actual ports on which
* the NameNode is up and running if the user passes the port as
* <code>zero</code> in the conf.
*
* @param conf confirguration
* @throws IOException
*/
public NameNode(Configuration conf) throws IOException {
this(FileSystem.getDefaultUri(conf).getAuthority(), conf);
}
/**
* Create a NameNode at the specified location and start it.
*
* The conf will be modified to reflect the actual ports on which
* the NameNode is up and running if the user passes the port as
* <code>zero</code>.
*/
public NameNode(String bindAddress,
Configuration conf
) throws IOException {
try {
initialize(bindAddress, conf);
} catch (IOException e) {
this.stop();
throw e;
}
}
/**
* Wait for service to finish.
* (Normally, it runs forever.)
*/
public void join() {
try {
this.server.join();
} catch (InterruptedException ie) {
}
}
/**
* Stop all NameNode threads and wait for all to finish.
*/
public void stop() {
if (stopRequested)
return;
stopRequested = true;
if(namesystem != null) namesystem.close();
if(emptier != null) emptier.interrupt();
if(server != null) server.stop();
if (myMetrics != null) {
myMetrics.shutdown();
}
if (namesystem != null) {
namesystem.shutdown();
}
}
/////////////////////////////////////////////////////
// NamenodeProtocol
/////////////////////////////////////////////////////
/**
* return a list of blocks & their locations on <code>datanode</code> whose
* total size is <code>size</code>
*
* @param datanode on which blocks are located
* @param size total size of blocks
*/
public BlocksWithLocations getBlocks(DatanodeInfo datanode, long size)
throws IOException {
if(size <= 0) {
throw new IllegalArgumentException(
"Unexpected not positive size: "+size);
}
return namesystem.getBlocks(datanode, size);
}
/////////////////////////////////////////////////////
// ClientProtocol
/////////////////////////////////////////////////////
/** {@inheritDoc} */
public LocatedBlocks getBlockLocations(String src,
long offset,
long length) throws IOException {
myMetrics.numGetBlockLocations.inc();
return namesystem.getBlockLocations(getClientMachine(),
src, offset, length);
}
private static String getClientMachine() {
String clientMachine = Server.getRemoteAddress();
if (clientMachine == null) {
clientMachine = "";
}
return clientMachine;
}
/** {@inheritDoc} */
public void create(String src,
FsPermission masked,
String clientName,
boolean overwrite,
short replication,
long blockSize
) throws IOException {
String clientMachine = getClientMachine();
if (stateChangeLog.isDebugEnabled()) {
stateChangeLog.debug("*DIR* NameNode.create: file "
+src+" for "+clientName+" at "+clientMachine);
}
if (!checkPathLength(src)) {
throw new IOException("create: Pathname too long. Limit "
+ MAX_PATH_LENGTH + " characters, " + MAX_PATH_DEPTH + " levels.");
}
namesystem.startFile(src,
new PermissionStatus(UserGroupInformation.getCurrentUGI().getUserName(),
null, masked),
clientName, clientMachine, overwrite, replication, blockSize);
myMetrics.numFilesCreated.inc();
myMetrics.numCreateFileOps.inc();
}
/** {@inheritDoc} */
public LocatedBlock append(String src, String clientName) throws IOException {
String clientMachine = getClientMachine();
if (stateChangeLog.isDebugEnabled()) {
stateChangeLog.debug("*DIR* NameNode.append: file "
+src+" for "+clientName+" at "+clientMachine);
}
if (supportAppends == false) {
throw new IOException("Append to hdfs not supported." +
" Please refer to dfs.support.append configuration parameter.");
}
LocatedBlock info = namesystem.appendFile(src, clientName, clientMachine);
myMetrics.numFilesAppended.inc();
return info;
}
/** {@inheritDoc} */
public boolean setReplication(String src,
short replication
) throws IOException {
return namesystem.setReplication(src, replication);
}
/** {@inheritDoc} */
public void setPermission(String src, FsPermission permissions
) throws IOException {
namesystem.setPermission(src, permissions);
}
/** {@inheritDoc} */
public void setOwner(String src, String username, String groupname
) throws IOException {
namesystem.setOwner(src, username, groupname);
}
/**
*/
public LocatedBlock addBlock(String src,
String clientName) throws IOException {
stateChangeLog.debug("*BLOCK* NameNode.addBlock: file "
+src+" for "+clientName);
LocatedBlock locatedBlock = namesystem.getAdditionalBlock(src, clientName);
if (locatedBlock != null)
myMetrics.numAddBlockOps.inc();
return locatedBlock;
}
/**
* The client needs to give up on the block.
*/
public void abandonBlock(Block b, String src, String holder
) throws IOException {
stateChangeLog.debug("*BLOCK* NameNode.abandonBlock: "
+b+" of file "+src);
if (!namesystem.abandonBlock(b, src, holder)) {
throw new IOException("Cannot abandon block during write to " + src);
}
}
/** {@inheritDoc} */
public boolean complete(String src, String clientName) throws IOException {
stateChangeLog.debug("*DIR* NameNode.complete: " + src + " for " + clientName);
CompleteFileStatus returnCode = namesystem.completeFile(src, clientName);
if (returnCode == CompleteFileStatus.STILL_WAITING) {
return false;
} else if (returnCode == CompleteFileStatus.COMPLETE_SUCCESS) {
return true;
} else {
throw new IOException("Could not complete write to file " + src + " by " + clientName);
}
}
/**
* The client has detected an error on the specified located blocks
* and is reporting them to the server. For now, the namenode will
* mark the block as corrupt. In the future we might
* check the blocks are actually corrupt.
*/
public void reportBadBlocks(LocatedBlock[] blocks) throws IOException {
stateChangeLog.info("*DIR* NameNode.reportBadBlocks");
for (int i = 0; i < blocks.length; i++) {
Block blk = blocks[i].getBlock();
DatanodeInfo[] nodes = blocks[i].getLocations();
for (int j = 0; j < nodes.length; j++) {
DatanodeInfo dn = nodes[j];
namesystem.markBlockAsCorrupt(blk, dn);
}
}
}
/** {@inheritDoc} */
public long nextGenerationStamp(Block block) throws IOException{
return namesystem.nextGenerationStampForBlock(block);
}
/** {@inheritDoc} */
public void commitBlockSynchronization(Block block,
long newgenerationstamp, long newlength,
boolean closeFile, boolean deleteblock, DatanodeID[] newtargets
) throws IOException {
namesystem.commitBlockSynchronization(block,
newgenerationstamp, newlength, closeFile, deleteblock, newtargets);
}
public long getPreferredBlockSize(String filename) throws IOException {
return namesystem.getPreferredBlockSize(filename);
}
/**
*/
public boolean rename(String src, String dst) throws IOException {
stateChangeLog.debug("*DIR* NameNode.rename: " + src + " to " + dst);
if (!checkPathLength(dst)) {
throw new IOException("rename: Pathname too long. Limit "
+ MAX_PATH_LENGTH + " characters, " + MAX_PATH_DEPTH + " levels.");
}
boolean ret = namesystem.renameTo(src, dst);
if (ret) {
myMetrics.numFilesRenamed.inc();
}
return ret;
}
/**
*/
@Deprecated
public boolean delete(String src) throws IOException {
return delete(src, true);
}
/** {@inheritDoc} */
public boolean delete(String src, boolean recursive) throws IOException {
if (stateChangeLog.isDebugEnabled()) {
stateChangeLog.debug("*DIR* Namenode.delete: src=" + src
+ ", recursive=" + recursive);
}
boolean ret = namesystem.delete(src, recursive);
if (ret)
myMetrics.numDeleteFileOps.inc();
return ret;
}
/**
* Check path length does not exceed maximum. Returns true if
* length and depth are okay. Returns false if length is too long
* or depth is too great.
*
*/
private boolean checkPathLength(String src) {
Path srcPath = new Path(src);
return (src.length() <= MAX_PATH_LENGTH &&
srcPath.depth() <= MAX_PATH_DEPTH);
}
/** {@inheritDoc} */
public boolean mkdirs(String src, FsPermission masked) throws IOException {
stateChangeLog.debug("*DIR* NameNode.mkdirs: " + src);
if (!checkPathLength(src)) {
throw new IOException("mkdirs: Pathname too long. Limit "
+ MAX_PATH_LENGTH + " characters, " + MAX_PATH_DEPTH + " levels.");
}
return namesystem.mkdirs(src,
new PermissionStatus(UserGroupInformation.getCurrentUGI().getUserName(),
null, masked));
}
/**
*/
public void renewLease(String clientName) throws IOException {
namesystem.renewLease(clientName);
}
/**
*/
public FileStatus[] getListing(String src) throws IOException {
FileStatus[] files = namesystem.getListing(src);
if (files != null) {
myMetrics.numGetListingOps.inc();
}
return files;
}
/**
* Get the file info for a specific file.
* @param src The string representation of the path to the file
* @throws IOException if permission to access file is denied by the system
* @return object containing information regarding the file
* or null if file not found
*/
public FileStatus getFileInfo(String src) throws IOException {
return namesystem.getFileInfo(src);
}
/** @inheritDoc */
public long[] getStats() throws IOException {
return namesystem.getStats();
}
/**
*/
public DatanodeInfo[] getDatanodeReport(DatanodeReportType type)
throws IOException {
DatanodeInfo results[] = namesystem.datanodeReport(type);
if (results == null ) {
throw new IOException("Cannot find datanode report");
}
return results;
}
/**
* @inheritDoc
*/
public boolean setSafeMode(SafeModeAction action) throws IOException {
return namesystem.setSafeMode(action);
}
/**
* Is the cluster currently in safe mode?
*/
public boolean isInSafeMode() {
return namesystem.isInSafeMode();
}
/*
* Refresh the list of datanodes that the namenode should allow to
* connect. Re-reads conf by creating new Configuration object and
* uses the files list in the configuration to update the list.
*/
public void refreshNodes() throws IOException {
namesystem.refreshNodes(new Configuration());
}
/**
* Returns the size of the current edit log.
*/
public long getEditLogSize() throws IOException {
return namesystem.getEditLogSize();
}
/**
* Roll the edit log.
*/
public CheckpointSignature rollEditLog() throws IOException {
return namesystem.rollEditLog();
}
/**
* Roll the image
*/
public void rollFsImage() throws IOException {
namesystem.rollFSImage();
}
public void finalizeUpgrade() throws IOException {
namesystem.finalizeUpgrade();
}
public UpgradeStatusReport distributedUpgradeProgress(UpgradeAction action
) throws IOException {
return namesystem.distributedUpgradeProgress(action);
}
/**
* Dumps namenode state into specified file
*/
public void metaSave(String filename) throws IOException {
namesystem.metaSave(filename);
}
/** {@inheritDoc} */
public ContentSummary getContentSummary(String path) throws IOException {
return namesystem.getContentSummary(path);
}
/** {@inheritDoc} */
public void setQuota(String path, long namespaceQuota, long diskspaceQuota)
throws IOException {
namesystem.setQuota(path, namespaceQuota, diskspaceQuota);
}
/** {@inheritDoc} */
public void fsync(String src, String clientName) throws IOException {
namesystem.fsync(src, clientName);
}
/** @inheritDoc */
public void setTimes(String src, long mtime, long atime) throws IOException {
namesystem.setTimes(src, mtime, atime);
}
////////////////////////////////////////////////////////////////
// DatanodeProtocol
////////////////////////////////////////////////////////////////
/**
*/
public DatanodeRegistration register(DatanodeRegistration nodeReg
) throws IOException {
verifyVersion(nodeReg.getVersion());
namesystem.registerDatanode(nodeReg);
return nodeReg;
}
/**
* Data node notify the name node that it is alive
* Return an array of block-oriented commands for the datanode to execute.
* This will be either a transfer or a delete operation.
*/
public DatanodeCommand[] sendHeartbeat(DatanodeRegistration nodeReg,
long capacity,
long dfsUsed,
long remaining,
int xmitsInProgress,
int xceiverCount) throws IOException {
verifyRequest(nodeReg);
return namesystem.handleHeartbeat(nodeReg, capacity, dfsUsed, remaining,
xceiverCount, xmitsInProgress);
}
public DatanodeCommand blockReport(DatanodeRegistration nodeReg,
long[] blocks) throws IOException {
verifyRequest(nodeReg);
BlockListAsLongs blist = new BlockListAsLongs(blocks);
stateChangeLog.debug("*BLOCK* NameNode.blockReport: "
+"from "+nodeReg.getName()+" "+blist.getNumberOfBlocks() +" blocks");
namesystem.processReport(nodeReg, blist);
if (getFSImage().isUpgradeFinalized())
return DatanodeCommand.FINALIZE;
return null;
}
public void blockReceived(DatanodeRegistration nodeReg,
Block blocks[],
String delHints[]) throws IOException {
verifyRequest(nodeReg);
stateChangeLog.debug("*BLOCK* NameNode.blockReceived: "
+"from "+nodeReg.getName()+" "+blocks.length+" blocks.");
for (int i = 0; i < blocks.length; i++) {
namesystem.blockReceived(nodeReg, blocks[i], delHints[i]);
}
}
/**
*/
public void errorReport(DatanodeRegistration nodeReg,
int errorCode,
String msg) throws IOException {
// Log error message from datanode
String dnName = (nodeReg == null ? "unknown DataNode" : nodeReg.getName());
LOG.info("Error report from " + dnName + ": " + msg);
if (errorCode == DatanodeProtocol.NOTIFY) {
return;
}
verifyRequest(nodeReg);
if (errorCode == DatanodeProtocol.DISK_ERROR) {
namesystem.removeDatanode(nodeReg);
}
}
public NamespaceInfo versionRequest() throws IOException {
return namesystem.getNamespaceInfo();
}
public UpgradeCommand processUpgradeCommand(UpgradeCommand comm) throws IOException {
return namesystem.processDistributedUpgradeCommand(comm);
}
/**
* Verify request.
*
* Verifies correctness of the datanode version, registration ID, and
* if the datanode does not need to be shutdown.
*
* @param nodeReg data node registration
* @throws IOException
*/
public void verifyRequest(DatanodeRegistration nodeReg) throws IOException {
verifyVersion(nodeReg.getVersion());
if (!namesystem.getRegistrationID().equals(nodeReg.getRegistrationID()))
throw new UnregisteredDatanodeException(nodeReg);
}
/**
* Verify version.
*
* @param version
* @throws IOException
*/
public void verifyVersion(int version) throws IOException {
if (version != LAYOUT_VERSION)
throw new IncorrectVersionException(version, "data node");
}
/**
* Returns the name of the fsImage file
*/
public File getFsImageName() throws IOException {
return getFSImage().getFsImageName();
}
public FSImage getFSImage() {
return namesystem.dir.fsImage;
}
/**
* Returns the name of the fsImage file uploaded by periodic
* checkpointing
*/
public File[] getFsImageNameCheckpoint() throws IOException {
return getFSImage().getFsImageNameCheckpoint();
}
/**
* Returns the address on which the NameNodes is listening to.
* @return the address on which the NameNodes is listening to.
*/
public InetSocketAddress getNameNodeAddress() {
return nameNodeAddress;
}
NetworkTopology getNetworkTopology() {
return this.namesystem.clusterMap;
}
/**
* Verify that configured directories exist, then
* Interactively confirm that formatting is desired
* for each existing directory and format them.
*
* @param conf
* @param isConfirmationNeeded
* @return true if formatting was aborted, false otherwise
* @throws IOException
*/
private static boolean format(Configuration conf,
boolean isConfirmationNeeded
) throws IOException {
Collection<File> dirsToFormat = FSNamesystem.getNamespaceDirs(conf);
Collection<File> editDirsToFormat =
FSNamesystem.getNamespaceEditsDirs(conf);
for(Iterator<File> it = dirsToFormat.iterator(); it.hasNext();) {
File curDir = it.next();
if (!curDir.exists())
continue;
if (isConfirmationNeeded) {
System.err.print("Re-format filesystem in " + curDir +" ? (Y or N) ");
if (!(System.in.read() == 'Y')) {
System.err.println("Format aborted in "+ curDir);
return true;
}
while(System.in.read() != '\n'); // discard the enter-key
}
}
FSNamesystem nsys = new FSNamesystem(new FSImage(dirsToFormat,
editDirsToFormat), conf);
nsys.dir.fsImage.format();
return false;
}
private static boolean finalize(Configuration conf,
boolean isConfirmationNeeded
) throws IOException {
Collection<File> dirsToFormat = FSNamesystem.getNamespaceDirs(conf);
Collection<File> editDirsToFormat =
FSNamesystem.getNamespaceEditsDirs(conf);
FSNamesystem nsys = new FSNamesystem(new FSImage(dirsToFormat,
editDirsToFormat), conf);
System.err.print(
"\"finalize\" will remove the previous state of the files system.\n"
+ "Recent upgrade will become permanent.\n"
+ "Rollback option will not be available anymore.\n");
if (isConfirmationNeeded) {
System.err.print("Finalize filesystem state ? (Y or N) ");
if (!(System.in.read() == 'Y')) {
System.err.println("Finalize aborted.");
return true;
}
while(System.in.read() != '\n'); // discard the enter-key
}
nsys.dir.fsImage.finalizeUpgrade();
return false;
}
private static void printUsage() {
System.err.println(
"Usage: java NameNode [" +
StartupOption.FORMAT.getName() + "] | [" +
StartupOption.UPGRADE.getName() + "] | [" +
StartupOption.ROLLBACK.getName() + "] | [" +
StartupOption.FINALIZE.getName() + "] | [" +
StartupOption.IMPORT.getName() + "]");
}
private static StartupOption parseArguments(String args[],
Configuration conf) {
int argsLen = (args == null) ? 0 : args.length;
StartupOption startOpt = StartupOption.REGULAR;
for(int i=0; i < argsLen; i++) {
String cmd = args[i];
if (StartupOption.FORMAT.getName().equalsIgnoreCase(cmd)) {
startOpt = StartupOption.FORMAT;
} else if (StartupOption.REGULAR.getName().equalsIgnoreCase(cmd)) {
startOpt = StartupOption.REGULAR;
} else if (StartupOption.UPGRADE.getName().equalsIgnoreCase(cmd)) {
startOpt = StartupOption.UPGRADE;
} else if (StartupOption.ROLLBACK.getName().equalsIgnoreCase(cmd)) {
startOpt = StartupOption.ROLLBACK;
} else if (StartupOption.FINALIZE.getName().equalsIgnoreCase(cmd)) {
startOpt = StartupOption.FINALIZE;
} else if (StartupOption.IMPORT.getName().equalsIgnoreCase(cmd)) {
startOpt = StartupOption.IMPORT;
} else
return null;
}
setStartupOption(conf, startOpt);
return startOpt;
}
private static void setStartupOption(Configuration conf, StartupOption opt) {
conf.set("dfs.namenode.startup", opt.toString());
}
static StartupOption getStartupOption(Configuration conf) {
return StartupOption.valueOf(conf.get("dfs.namenode.startup",
StartupOption.REGULAR.toString()));
}
public static NameNode createNameNode(String argv[],
Configuration conf) throws IOException {
if (conf == null)
conf = new Configuration();
StartupOption startOpt = parseArguments(argv, conf);
if (startOpt == null) {
printUsage();
return null;
}
switch (startOpt) {
case FORMAT:
boolean aborted = format(conf, true);
System.exit(aborted ? 1 : 0);
case FINALIZE:
aborted = finalize(conf, true);
System.exit(aborted ? 1 : 0);
default:
}
NameNode namenode = new NameNode(conf);
return namenode;
}
/**
*/
public static void main(String argv[]) throws Exception {
try {
StringUtils.startupShutdownMessage(NameNode.class, argv, LOG);
NameNode namenode = createNameNode(argv, null);
if (namenode != null)
namenode.join();
} catch (Throwable e) {
LOG.error(StringUtils.stringifyException(e));
System.exit(-1);
}
}
}