org.apache.hadoop.hdfs.server.namenode.NameNode Maven / Gradle / Ivy
/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.hadoop.hdfs.server.namenode;
import static org.apache.hadoop.fs.CommonConfigurationKeysPublic.FS_DEFAULT_NAME_KEY;
import static org.apache.hadoop.hdfs.DFSConfigKeys.*;
import java.io.File;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.URI;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.HadoopIllegalArgumentException;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.CommonConfigurationKeys;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.FileUtil;
import org.apache.hadoop.fs.Trash;
import org.apache.hadoop.hdfs.DFSUtil;
import org.apache.hadoop.hdfs.HdfsConfiguration;
import org.apache.hadoop.hdfs.protocol.HdfsConstants;
import org.apache.hadoop.hdfs.server.common.HdfsServerConstants.NamenodeRole;
import org.apache.hadoop.hdfs.server.common.HdfsServerConstants.StartupOption;
import org.apache.hadoop.hdfs.server.namenode.metrics.NameNodeMetrics;
import org.apache.hadoop.hdfs.server.protocol.NamenodeProtocols;
import org.apache.hadoop.hdfs.server.protocol.NamenodeRegistration;
import org.apache.hadoop.metrics2.lib.DefaultMetricsSystem;
import org.apache.hadoop.net.NetUtils;
import org.apache.hadoop.security.SecurityUtil;
import org.apache.hadoop.security.UserGroupInformation;
import org.apache.hadoop.util.ServicePlugin;
import org.apache.hadoop.util.StringUtils;
import static org.apache.hadoop.util.ExitUtil.terminate;
/**********************************************************
* 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, or when using federated NameNodes.)
*
* 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 and the HTTP server to the outside world,
* plus some configuration management.
*
* NameNode implements the
* {@link org.apache.hadoop.hdfs.protocol.ClientProtocol} interface, which
* allows clients to ask for DFS services.
* {@link org.apache.hadoop.hdfs.protocol.ClientProtocol} is not designed for
* direct use by authors of DFS client code. End-users should instead use the
* {@link org.apache.hadoop.fs.FileSystem} class.
*
* NameNode also implements the
* {@link org.apache.hadoop.hdfs.server.protocol.DatanodeProtocol} interface,
* used by DataNodes 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
* {@link org.apache.hadoop.hdfs.server.protocol.NamenodeProtocol} interface,
* used by secondary namenodes or rebalancing processes to get partial
* NameNode state, for example partial blocksMap etc.
**********************************************************/
@InterfaceAudience.Private
public class NameNode {
static{
HdfsConfiguration.init();
}
/**
* HDFS federation configuration can have two types of parameters:
*
* - Parameter that is common for all the name services in the cluster.
* - Parameters that are specific to a name service. This keys are suffixed
* with nameserviceId in the configuration. For example,
* "dfs.namenode.rpc-address.nameservice1".
*
*
* Following are nameservice specific keys.
*/
public static final String[] NAMESERVICE_SPECIFIC_KEYS = {
DFS_NAMENODE_RPC_ADDRESS_KEY,
DFS_NAMENODE_NAME_DIR_KEY,
DFS_NAMENODE_EDITS_DIR_KEY,
DFS_NAMENODE_CHECKPOINT_DIR_KEY,
DFS_NAMENODE_CHECKPOINT_EDITS_DIR_KEY,
DFS_NAMENODE_SERVICE_RPC_ADDRESS_KEY,
DFS_NAMENODE_HTTP_ADDRESS_KEY,
DFS_NAMENODE_HTTPS_ADDRESS_KEY,
DFS_NAMENODE_KEYTAB_FILE_KEY,
DFS_NAMENODE_SECONDARY_HTTP_ADDRESS_KEY,
DFS_NAMENODE_SECONDARY_HTTPS_PORT_KEY,
DFS_SECONDARY_NAMENODE_KEYTAB_FILE_KEY,
DFS_NAMENODE_BACKUP_ADDRESS_KEY,
DFS_NAMENODE_BACKUP_HTTP_ADDRESS_KEY,
DFS_NAMENODE_BACKUP_SERVICE_RPC_ADDRESS_KEY
};
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 static final Log blockStateChangeLog = LogFactory.getLog("BlockStateChange");
protected FSNamesystem namesystem;
protected NamenodeRole role;
/** httpServer */
protected NameNodeHttpServer httpServer;
private Thread emptier;
/** only used for testing purposes */
protected boolean stopRequested = false;
/** Registration information of this name-node */
protected NamenodeRegistration nodeRegistration;
/** Activated plug-ins. */
private List plugins;
private NameNodeRpcServer rpcServer;
/** 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 metrics;
/** Return the {@link FSNamesystem} object.
* @return {@link FSNamesystem} object.
*/
public FSNamesystem getNamesystem() {
return namesystem;
}
public NamenodeProtocols getRpcServer() {
return rpcServer;
}
static void initMetrics(Configuration conf, NamenodeRole role) {
metrics = NameNodeMetrics.create(conf, role);
}
public static NameNodeMetrics getNameNodeMetrics() {
return metrics;
}
public static InetSocketAddress getAddress(String address) {
return NetUtils.createSocketAddr(address, DEFAULT_PORT);
}
/**
* Set the configuration property for the service rpc address
* to address
*/
public static void setServiceAddress(Configuration conf,
String address) {
LOG.info("Setting ADDRESS " + address);
conf.set(DFS_NAMENODE_SERVICE_RPC_ADDRESS_KEY, address);
}
/**
* Fetches the address for services to use when connecting to namenode
* based on the value of fallback returns null if the special
* address is not specified or returns the default namenode address
* to be used by both clients and services.
* Services here are datanodes, backup node, any non client connection
*/
public static InetSocketAddress getServiceAddress(Configuration conf,
boolean fallback) {
String addr = conf.get(DFS_NAMENODE_SERVICE_RPC_ADDRESS_KEY);
if (addr == null || addr.isEmpty()) {
return fallback ? getAddress(conf) : null;
}
return getAddress(addr);
}
public static InetSocketAddress getAddress(Configuration conf) {
URI filesystemURI = FileSystem.getDefaultUri(conf);
return getAddress(filesystemURI);
}
/**
* TODO:FEDERATION
* @param filesystemURI
* @return address of file system
*/
static InetSocketAddress getAddress(URI filesystemURI) {
String authority = filesystemURI.getAuthority();
if (authority == null) {
throw new IllegalArgumentException(String.format(
"Invalid URI for NameNode address (check %s): %s has no authority.",
FileSystem.FS_DEFAULT_NAME_KEY, filesystemURI.toString()));
}
if (!HdfsConstants.HDFS_URI_SCHEME.equalsIgnoreCase(
filesystemURI.getScheme())) {
throw new IllegalArgumentException(String.format(
"Invalid URI for NameNode address (check %s): %s is not of scheme '%s'.",
FileSystem.FS_DEFAULT_NAME_KEY, filesystemURI.toString(),
HdfsConstants.HDFS_URI_SCHEME));
}
return getAddress(authority);
}
public static URI getUri(InetSocketAddress namenode) {
int port = namenode.getPort();
String portString = port == DEFAULT_PORT ? "" : (":"+port);
return URI.create(HdfsConstants.HDFS_URI_SCHEME + "://"
+ namenode.getHostName()+portString);
}
/**
* Compose a "host:port" string from the address.
*/
public static String getHostPortString(InetSocketAddress addr) {
return addr.getHostName() + ":" + addr.getPort();
}
//
// Common NameNode methods implementation for the active name-node role.
//
public NamenodeRole getRole() {
return role;
}
boolean isRole(NamenodeRole that) {
return role.equals(that);
}
/**
* Given a configuration get the address of the service rpc server
* If the service rpc is not configured returns null
*/
protected InetSocketAddress getServiceRpcServerAddress(Configuration conf)
throws IOException {
return NameNode.getServiceAddress(conf, false);
}
protected InetSocketAddress getRpcServerAddress(Configuration conf) throws IOException {
return getAddress(conf);
}
/**
* Modifies the configuration passed to contain the service rpc address setting
*/
protected void setRpcServiceServerAddress(Configuration conf,
InetSocketAddress serviceRPCAddress) {
setServiceAddress(conf, getHostPortString(serviceRPCAddress));
}
protected void setRpcServerAddress(Configuration conf,
InetSocketAddress rpcAddress) {
FileSystem.setDefaultUri(conf, getUri(rpcAddress));
}
protected InetSocketAddress getHttpServerAddress(Configuration conf) {
return getHttpAddress(conf);
}
/** @return the NameNode HTTP address set in the conf. */
public static InetSocketAddress getHttpAddress(Configuration conf) {
return NetUtils.createSocketAddr(
conf.get(DFS_NAMENODE_HTTP_ADDRESS_KEY, DFS_NAMENODE_HTTP_ADDRESS_DEFAULT));
}
protected void setHttpServerAddress(Configuration conf) {
conf.set(DFS_NAMENODE_HTTP_ADDRESS_KEY,
getHostPortString(getHttpAddress()));
}
protected void loadNamesystem(Configuration conf) throws IOException {
this.namesystem = new FSNamesystem(conf);
}
NamenodeRegistration getRegistration() {
return nodeRegistration;
}
NamenodeRegistration setRegistration() {
nodeRegistration = new NamenodeRegistration(
getHostPortString(rpcServer.getRpcAddress()),
getHostPortString(getHttpAddress()),
getFSImage().getStorage(), getRole());
return nodeRegistration;
}
/**
* Login as the configured user for the NameNode.
*/
void loginAsNameNodeUser(Configuration conf) throws IOException {
InetSocketAddress socAddr = getRpcServerAddress(conf);
SecurityUtil.login(conf, DFS_NAMENODE_KEYTAB_FILE_KEY,
DFS_NAMENODE_USER_NAME_KEY, socAddr.getHostName());
}
/**
* Initialize name-node.
*
* @param conf the configuration
*/
protected void initialize(Configuration conf) throws IOException {
UserGroupInformation.setConfiguration(conf);
loginAsNameNodeUser(conf);
NameNode.initMetrics(conf, this.getRole());
loadNamesystem(conf);
rpcServer = createRpcServer(conf);
try {
validateConfigurationSettings(conf);
} catch (IOException e) {
LOG.fatal(e.toString());
throw e;
}
activate(conf);
LOG.info(getRole() + " up at: " + rpcServer.getRpcAddress());
if (rpcServer.getServiceRpcAddress() != null) {
LOG.info(getRole() + " service server is up at: " + rpcServer.getServiceRpcAddress());
}
}
/**
* Create the RPC server implementation. Used as an extension point for the
* BackupNode.
*/
protected NameNodeRpcServer createRpcServer(Configuration conf)
throws IOException {
return new NameNodeRpcServer(conf, this);
}
/**
* Verifies that the final Configuration Settings look ok for the NameNode to
* properly start up
* Things to check for include:
* - HTTP Server Port does not equal the RPC Server Port
* @param conf
* @throws IOException
*/
protected void validateConfigurationSettings(final Configuration conf)
throws IOException {
// check to make sure the web port and rpc port do not match
if(getHttpServerAddress(conf).getPort()
== getRpcServerAddress(conf).getPort()) {
String errMsg = "dfs.namenode.rpc-address " +
"("+ getRpcServerAddress(conf) + ") and " +
"dfs.namenode.http-address ("+ getHttpServerAddress(conf) + ") " +
"configuration keys are bound to the same port, unable to start " +
"NameNode. Port: " + getRpcServerAddress(conf).getPort();
throw new IOException(errMsg);
}
}
/**
* Activate name-node servers and threads.
*/
void activate(Configuration conf) throws IOException {
if ((isRole(NamenodeRole.NAMENODE))
&& (UserGroupInformation.isSecurityEnabled())) {
namesystem.activateSecretManager();
}
namesystem.activate(conf);
startHttpServer(conf);
rpcServer.start();
startTrashEmptier(conf);
plugins = conf.getInstances(DFS_NAMENODE_PLUGINS_KEY,
ServicePlugin.class);
for (ServicePlugin p: plugins) {
try {
p.start(this);
} catch (Throwable t) {
LOG.warn("ServicePlugin " + p + " could not be started", t);
}
}
}
private void startTrashEmptier(Configuration conf) throws IOException {
long trashInterval
= conf.getLong(CommonConfigurationKeys.FS_TRASH_INTERVAL_KEY,
CommonConfigurationKeys.FS_TRASH_INTERVAL_DEFAULT);
if(trashInterval == 0)
return;
this.emptier = new Thread(new Trash(conf).getEmptier(), "Trash Emptier");
this.emptier.setDaemon(true);
this.emptier.start();
}
private void startHttpServer(final Configuration conf) throws IOException {
httpServer = new NameNodeHttpServer(conf, this, getHttpServerAddress(conf));
httpServer.start();
setHttpServerAddress(conf);
}
/**
* Start NameNode.
*
* The name-node can be started with one of the following startup options:
*
* - {@link StartupOption#REGULAR REGULAR} - normal name node startup
* - {@link StartupOption#FORMAT FORMAT} - format name node
* - {@link StartupOption#BACKUP BACKUP} - start backup node
* - {@link StartupOption#CHECKPOINT CHECKPOINT} - start checkpoint node
* - {@link StartupOption#UPGRADE UPGRADE} - start the cluster
* upgrade and create a snapshot of the current file system state
* - {@link StartupOption#ROLLBACK ROLLBACK} - roll the
* cluster back to the previous state
* - {@link StartupOption#FINALIZE FINALIZE} - finalize
* previous upgrade
* - {@link StartupOption#IMPORT IMPORT} - import checkpoint
*
* The option is passed via configuration field:
* dfs.namenode.startup
*
* 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
* zero in the conf.
*
* @param conf confirguration
* @throws IOException
*/
public NameNode(Configuration conf) throws IOException {
this(conf, NamenodeRole.NAMENODE);
}
protected NameNode(Configuration conf, NamenodeRole role)
throws IOException {
this.role = role;
try {
initializeGenericKeys(conf, getNameServiceId(conf));
initialize(conf);
} catch (IOException e) {
this.stop();
throw e;
} catch (HadoopIllegalArgumentException e) {
this.stop();
throw e;
}
}
/**
* Wait for service to finish.
* (Normally, it runs forever.)
*/
public void join() {
try {
this.rpcServer.join();
} catch (InterruptedException ie) {
}
}
/**
* Stop all NameNode threads and wait for all to finish.
*/
public void stop() {
synchronized(this) {
if (stopRequested)
return;
stopRequested = true;
}
if (plugins != null) {
for (ServicePlugin p : plugins) {
try {
p.stop();
} catch (Throwable t) {
LOG.warn("ServicePlugin " + p + " could not be stopped", t);
}
}
}
try {
if (httpServer != null) httpServer.stop();
} catch (Exception e) {
LOG.error("Exception while stopping httpserver", e);
}
if(namesystem != null) namesystem.close();
if(emptier != null) emptier.interrupt();
if(rpcServer != null) rpcServer.stop();
if (metrics != null) {
metrics.shutdown();
}
if (namesystem != null) {
namesystem.shutdown();
}
}
synchronized boolean isStopRequested() {
return stopRequested;
}
/**
* Is the cluster currently in safe mode?
*/
public boolean isInSafeMode() {
return namesystem.isInSafeMode();
}
/** get FSImage */
FSImage getFSImage() {
return namesystem.dir.fsImage;
}
/**
* Returns the address on which the NameNodes is listening to.
* @return namenode rpc address
*/
public InetSocketAddress getNameNodeAddress() {
return rpcServer.getRpcAddress();
}
/**
* Returns namenode service rpc address, if set. Otherwise returns
* namenode rpc address.
* @return namenode service rpc address used by datanodes
*/
public InetSocketAddress getServiceRpcAddress() {
return rpcServer.getServiceRpcAddress() != null ? rpcServer.getServiceRpcAddress() : rpcServer.getRpcAddress();
}
/**
* Returns the address of the NameNodes http server,
* which is used to access the name-node web UI.
*
* @return the http address.
*/
public InetSocketAddress getHttpAddress() {
return httpServer.getHttpAddress();
}
/**
* 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 {
if (!conf.getBoolean(DFS_NAMENODE_SUPPORT_ALLOW_FORMAT_KEY,
DFS_NAMENODE_SUPPORT_ALLOW_FORMAT_DEFAULT)) {
throw new IOException("The option " + DFS_NAMENODE_SUPPORT_ALLOW_FORMAT_KEY
+ " is set to false for this filesystem, so it "
+ "cannot be formatted. You will need to set "
+ DFS_NAMENODE_SUPPORT_ALLOW_FORMAT_KEY +" parameter "
+ "to true in order to format this filesystem");
}
Collection dirsToFormat = FSNamesystem.getNamespaceDirs(conf);
Collection editDirsToFormat =
FSNamesystem.getNamespaceEditsDirs(conf);
for(Iterator it = dirsToFormat.iterator(); it.hasNext();) {
File curDir = new File(it.next().getPath());
// Its alright for a dir not to exist, or to exist (properly accessible)
// and be completely empty.
if (!curDir.exists() ||
(curDir.isDirectory() && FileUtil.listFiles(curDir).length == 0))
continue;
if (isConfirmationNeeded) {
if (!confirmPrompt("Re-format filesystem in " + curDir + " ?")) {
System.err.println("Format aborted in "+ curDir);
return true;
}
}
}
// if clusterID is not provided - see if you can find the current one
String clusterId = StartupOption.FORMAT.getClusterId();
if(clusterId == null || clusterId.equals("")) {
//Generate a new cluster id
clusterId = NNStorage.newClusterID();
}
System.out.println("Formatting using clusterid: " + clusterId);
FSImage fsImage = new FSImage(conf, null, dirsToFormat, editDirsToFormat);
FSNamesystem nsys = new FSNamesystem(fsImage, conf);
nsys.dir.fsImage.format(clusterId);
return false;
}
private static boolean finalize(Configuration conf,
boolean isConfirmationNeeded
) throws IOException {
FSNamesystem nsys = new FSNamesystem(new FSImage(conf), 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) {
if (!confirmPrompt("Finalize filesystem state?")) {
System.err.println("Finalize aborted.");
return true;
}
}
nsys.dir.fsImage.finalizeUpgrade();
return false;
}
private static void printUsage() {
System.err.println(
"Usage: java NameNode [" +
StartupOption.BACKUP.getName() + "] | [" +
StartupOption.CHECKPOINT.getName() + "] | [" +
StartupOption.FORMAT.getName() + "[" + StartupOption.CLUSTERID.getName() +
" cid ]] | [" +
StartupOption.UPGRADE.getName() + "] | [" +
StartupOption.ROLLBACK.getName() + "] | [" +
StartupOption.FINALIZE.getName() + "] | [" +
StartupOption.IMPORT.getName() + "]");
}
private static StartupOption parseArguments(String args[]) {
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;
// might be followed by two args
if (i + 2 < argsLen
&& args[i + 1].equalsIgnoreCase(StartupOption.CLUSTERID.getName())) {
i += 2;
startOpt.setClusterId(args[i]);
}
} else if (StartupOption.GENCLUSTERID.getName().equalsIgnoreCase(cmd)) {
startOpt = StartupOption.GENCLUSTERID;
} else if (StartupOption.REGULAR.getName().equalsIgnoreCase(cmd)) {
startOpt = StartupOption.REGULAR;
} else if (StartupOption.BACKUP.getName().equalsIgnoreCase(cmd)) {
startOpt = StartupOption.BACKUP;
} else if (StartupOption.CHECKPOINT.getName().equalsIgnoreCase(cmd)) {
startOpt = StartupOption.CHECKPOINT;
} else if (StartupOption.UPGRADE.getName().equalsIgnoreCase(cmd)) {
startOpt = StartupOption.UPGRADE;
// might be followed by two args
if (i + 2 < argsLen
&& args[i + 1].equalsIgnoreCase(StartupOption.CLUSTERID.getName())) {
i += 2;
startOpt.setClusterId(args[i]);
}
} 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;
}
return startOpt;
}
private static void setStartupOption(Configuration conf, StartupOption opt) {
conf.set(DFS_NAMENODE_STARTUP_KEY, opt.toString());
}
static StartupOption getStartupOption(Configuration conf) {
return StartupOption.valueOf(conf.get(DFS_NAMENODE_STARTUP_KEY,
StartupOption.REGULAR.toString()));
}
/**
* Print out a prompt to the user, and return true if the user
* responds with "Y" or "yes".
*/
static boolean confirmPrompt(String prompt) throws IOException {
while (true) {
System.err.print(prompt + " (Y or N) ");
StringBuilder responseBuilder = new StringBuilder();
while (true) {
int c = System.in.read();
if (c == -1 || c == '\r' || c == '\n') {
break;
}
responseBuilder.append((char)c);
}
String response = responseBuilder.toString();
if (response.equalsIgnoreCase("y") ||
response.equalsIgnoreCase("yes")) {
return true;
} else if (response.equalsIgnoreCase("n") ||
response.equalsIgnoreCase("no")) {
return false;
}
// else ask them again
}
}
public static NameNode createNameNode(String argv[], Configuration conf)
throws IOException {
if (conf == null)
conf = new HdfsConfiguration();
StartupOption startOpt = parseArguments(argv);
if (startOpt == null) {
printUsage();
return null;
}
setStartupOption(conf, startOpt);
switch (startOpt) {
case FORMAT:
boolean aborted = format(conf, true);
terminate(aborted ? 1 : 0);
return null; // avoid javac warning
case GENCLUSTERID:
System.err.println("Generating new cluster id:");
System.out.println(NNStorage.newClusterID());
terminate(0);
return null;
case FINALIZE:
aborted = finalize(conf, true);
terminate(aborted ? 1 : 0);
return null; // avoid javac warning
case BACKUP:
case CHECKPOINT:
NamenodeRole role = startOpt.toNodeRole();
DefaultMetricsSystem.initialize(role.toString().replace(" ", ""));
return new BackupNode(conf, role);
default: {
DefaultMetricsSystem.initialize("NameNode");
return new NameNode(conf);
}
}
}
/**
* In federation configuration is set for a set of
* namenode and secondary namenode/backup/checkpointer, which are
* grouped under a logical nameservice ID. The configuration keys specific
* to them have suffix set to configured nameserviceId.
*
* This method copies the value from specific key of format key.nameserviceId
* to key, to set up the generic configuration. Once this is done, only
* generic version of the configuration is read in rest of the code, for
* backward compatibility and simpler code changes.
*
* @param conf
* Configuration object to lookup specific key and to set the value
* to the key passed. Note the conf object is modified
* @param nameserviceId name service Id
* @see DFSUtil#setGenericConf(Configuration, String, String...)
*/
public static void initializeGenericKeys(Configuration conf, String
nameserviceId) {
if ((nameserviceId == null) || nameserviceId.isEmpty()) {
return;
}
DFSUtil.setGenericConf(conf, nameserviceId, NAMESERVICE_SPECIFIC_KEYS);
if (conf.get(DFS_NAMENODE_RPC_ADDRESS_KEY) != null) {
URI defaultUri = URI.create(HdfsConstants.HDFS_URI_SCHEME + "://"
+ conf.get(DFS_NAMENODE_RPC_ADDRESS_KEY));
conf.set(FS_DEFAULT_NAME_KEY, defaultUri.toString());
}
}
/**
* Get the name service Id for the node
* @return name service Id or null if federation is not configured
*/
protected String getNameServiceId(Configuration conf) {
return DFSUtil.getNamenodeNameServiceId(conf);
}
/**
*/
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.fatal("Exception in namenode join", e);
terminate(1);
}
}
}
© 2015 - 2025 Weber Informatics LLC | Privacy Policy