Index: conf/hadoop-default.xml
===================================================================
--- conf/hadoop-default.xml (revision 439206)
+++ conf/hadoop-default.xml (working copy)
@@ -38,6 +38,40 @@
creations/deletions), or "all".
+
+
+
+ mapred.tasktracker.dns.interface
+ default
+ The name of the Network Interface from which a task tracker should
+ report its IP address.
+
+
+
+
+ mapred.tasktracker.dns.nameserver
+ default
+ The host name or IP address of the name server (DNS) which a TaskTracker should
+ use to determine the host name used by the JobTracker for communication and display purposes.
+
+
+
+
+ dfs.datanode.dns.interface
+ default
+ The name of the Network Interface from which a data node should
+ report its IP address.
+
+
+
+
+ dfs.datanode.dns.nameserver
+ default
+ The host name or IP address of the name server (DNS) which a DataNode should
+ use to determine the host name used by the NameNode for communication and display purposes.
+
+
+
Index: src/java/org/apache/hadoop/net/DNS.java
===================================================================
--- src/java/org/apache/hadoop/net/DNS.java (revision 0)
+++ src/java/org/apache/hadoop/net/DNS.java (revision 0)
@@ -0,0 +1,187 @@
+package org.apache.hadoop.net;
+
+import java.io.IOException;
+import java.net.InetAddress;
+import java.net.NetworkInterface;
+import java.net.SocketException;
+import java.net.UnknownHostException;
+import java.util.Enumeration;
+import java.util.Vector;
+
+import javax.naming.NamingException;
+import javax.naming.directory.Attributes;
+import javax.naming.directory.DirContext;
+import javax.naming.directory.InitialDirContext;
+
+/**
+ *
+ * A class that provides direct and reverse lookup functionalities, allowing the
+ * querying of specific network interfaces or nameservers.
+ *
+ * @author Lorenzo Thione
+ *
+ */
+public class DNS {
+
+ /**
+ * Returns the hostname associated with the specified IP address by the
+ * provided nameserver.
+ *
+ * @param hostIp
+ * The address to reverse lookup
+ * @param ns
+ * The host name of a reachable DNS server
+ * @return The host name associated with the provided IP
+ * @throws NamingException
+ * If a NamingException is encountered
+ */
+ public static String reverseDns(InetAddress hostIp, String ns)
+ throws NamingException {
+ //
+ // Builds the reverse IP lookup form
+ // This is formed by reversing the IP numbers and appending in-addr.arpa
+ //
+ String[] parts = hostIp.getHostAddress().split("\\.");
+ String reverseIP = parts[3] + "." + parts[2] + "." + parts[1] + "."
+ + parts[0] + ".in-addr.arpa";
+
+ DirContext ictx = new InitialDirContext();
+ Attributes attribute = ictx.getAttributes("dns://"
+ + ((ns == null) ? "" : ns) + // Use "dns:///" if the default
+ // nameserver is to be used
+ "/" + reverseIP, new String[] { "PTR" });
+ ictx.close();
+
+ return attribute.get("PTR").get().toString();
+ }
+
+ /**
+ * Returns all the IPs associated with the provided interface, if any, in
+ * textual form.
+ *
+ * @param strInterface
+ * The name of the network interface to query (e.g. eth0)
+ * @return A string vector of all the IPs associated with the provided
+ * interface
+ * @throws UnknownHostException
+ * If an UnknownHostException is encountered in querying the
+ * default interface
+ *
+ */
+ public static String[] getIPs(String strInterface)
+ throws UnknownHostException {
+ try {
+ NetworkInterface netIF = NetworkInterface.getByName(strInterface);
+ if (netIF == null)
+ return new String[] { InetAddress.getLocalHost()
+ .getHostAddress() };
+ else {
+ Vector ips = new Vector();
+ Enumeration e = netIF.getInetAddresses();
+ while (e.hasMoreElements())
+ ips.add(((InetAddress) e.nextElement()).getHostAddress());
+ return (String[]) ips.toArray(new String[] {});
+ }
+ } catch (SocketException e) {
+ return new String[] { InetAddress.getLocalHost().getHostAddress() };
+ }
+ }
+
+ /**
+ * Returns the first available IP address associated with the provided
+ * network interface
+ *
+ * @param strInterface
+ * The name of the network interface to query (e.g. eth0)
+ * @return The IP address in text form
+ * @throws UnknownHostException
+ * If one is encountered in querying the default interface
+ */
+ public static String getDefaultIP(String strInterface)
+ throws UnknownHostException {
+ String[] ips = getIPs(strInterface);
+ return ips[0];
+ }
+
+ /**
+ * Returns all the host names associated by the provided nameserver with the
+ * address bound to the specified network interface
+ *
+ * @param strInterface
+ * The name of the network interface to query (e.g. eth0)
+ * @param nameserver
+ * The DNS host name
+ * @return A string vector of all host names associated with the IPs tied to
+ * the specified interface
+ * @throws UnknownHostException
+ */
+ public static String[] getHosts(String strInterface, String nameserver)
+ throws UnknownHostException {
+ String[] ips = getIPs(strInterface);
+ Vector hosts = new Vector();
+ for (int ctr = 0; ctr < ips.length; ctr++)
+ try {
+ hosts.add(reverseDns(InetAddress.getByName(ips[ctr]),
+ nameserver));
+ } catch (Exception e) {
+ }
+
+ if (hosts.size() == 0)
+ return new String[] { InetAddress.getLocalHost().getHostName() };
+ else
+ return (String[]) hosts.toArray(new String[] {});
+ }
+
+ /**
+ * Returns all the host names associated by the default nameserver with the
+ * address bound to the specified network interface
+ *
+ * @param strInterface
+ * The name of the network interface to query (e.g. eth0)
+ * @return The list of host names associated with IPs bound to the network
+ * interface
+ * @throws UnknownHostException
+ * If one is encountered while querying the deault interface
+ *
+ */
+ public static String[] getHosts(String strInterface)
+ throws UnknownHostException {
+ return getHosts(strInterface, null);
+ }
+
+ /**
+ * Returns the default (first) host name associated by the provided
+ * nameserver with the address bound to the specified network interface
+ *
+ * @param strInterface
+ * The name of the network interface to query (e.g. eth0)
+ * @param nameserver
+ * The DNS host name
+ * @return The default host names associated with IPs bound to the network
+ * interface
+ * @throws UnknownHostException
+ * If one is encountered while querying the deault interface
+ */
+ public static String getDefaultHost(String strInterface, String nameserver)
+ throws UnknownHostException {
+ String[] hosts = getHosts(strInterface, nameserver);
+ return hosts[0];
+ }
+
+ /**
+ * Returns the default (first) host name associated by the default
+ * nameserver with the address bound to the specified network interface
+ *
+ * @param strInterface
+ * The name of the network interface to query (e.g. eth0)
+ * @return The default host name associated with IPs bound to the network
+ * interface
+ * @throws UnknownHostException
+ * If one is encountered while querying the deault interface
+ */
+ public static String getDefaultHost(String strInterface)
+ throws UnknownHostException {
+ return getDefaultHost(strInterface, null);
+ }
+
+}
Index: src/java/org/apache/hadoop/net/package.html
===================================================================
--- src/java/org/apache/hadoop/net/package.html (revision 0)
+++ src/java/org/apache/hadoop/net/package.html (revision 0)
@@ -0,0 +1,5 @@
+
+
+Network-related classes.
+
+
Index: src/java/org/apache/hadoop/mapred/TaskTracker.java
===================================================================
--- src/java/org/apache/hadoop/mapred/TaskTracker.java (revision 439206)
+++ src/java/org/apache/hadoop/mapred/TaskTracker.java (working copy)
@@ -31,6 +31,7 @@
import org.apache.hadoop.metrics.ContextFactory;
import org.apache.hadoop.metrics.MetricsContext;
import org.apache.hadoop.metrics.MetricsRecord;
+import org.apache.hadoop.net.DNS;
/*******************************************************
* TaskTracker is a process that starts and tracks MR Tasks
@@ -154,8 +155,19 @@
* close().
*/
synchronized void initialize() throws IOException {
- this.localHostname = InetAddress.getLocalHost().getHostName();
+ // Gets the network interface and nameserver from the cluster configuration parameters
+ String nif = this.fConf.get("mapred.tasktracker.dns.interface", "default");
+ String ns = this.fConf.get("mapred.tasktracker.dns.nameserver", "default");
+ //If default, report localHost() name, otherwise user reverse lookup from DNS and nif
+ if (nif.equals("default"))
+ this.localHostname = InetAddress.getLocalHost().getHostName();
+ else
+ this.localHostname = ns.equals("default") ?
+ DNS.getDefaultHost(nif) :
+ DNS.getDefaultHost(nif, ns);
+
+
//check local disk
checkLocalDirs(this.fConf.getLocalDirs());
fConf.deleteLocalFiles(SUBDIR);
Index: src/java/org/apache/hadoop/dfs/DataNode.java
===================================================================
--- src/java/org/apache/hadoop/dfs/DataNode.java (revision 439206)
+++ src/java/org/apache/hadoop/dfs/DataNode.java (working copy)
@@ -15,21 +15,21 @@
*/
package org.apache.hadoop.dfs;
+import java.io.*;
+import java.net.*;
+import java.util.*;
+
import org.apache.commons.logging.*;
-
import org.apache.hadoop.ipc.*;
-import org.apache.hadoop.conf.*;
+import org.apache.hadoop.util.*;
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.mapred.StatusHttpServer;
import org.apache.hadoop.metrics.Metrics;
-import org.apache.hadoop.util.*;
+import org.apache.hadoop.metrics.MetricsRecord;
+import org.apache.hadoop.net.DNS;
import org.apache.hadoop.util.DiskChecker.DiskErrorException;
import org.apache.hadoop.util.DiskChecker.DiskOutOfSpaceException;
-import org.apache.hadoop.mapred.StatusHttpServer;
-import java.io.*;
-import java.net.*;
-import java.util.*;
-import org.apache.hadoop.metrics.MetricsRecord;
-
/**********************************************************
* DataNode is a class (and program) that stores a set of
* blocks for a DFS deployment. A single deployment can
@@ -179,6 +179,21 @@
File datadir,
InetSocketAddress nameNodeAddr,
Configuration conf ) throws IOException {
+
+ // Machine name is set to getlocalHost().getHostName(), so leave it unchanged unless
+ // the conf files contain network cluster parameters for this
+
+ // Gets the network interface and nameserver from the cluster configuration parameters
+ String nif = conf.get("dfs.datanode.dns.interface", "default");
+ String ns = conf.get("dfs.datanode.dns.nameserver", "default");
+
+
+ //If default, report localHost() name, otherwise user reverse lookup from DNS and nif
+ if (!nif.equals("default"))
+ machineName = ns.equals("default") ?
+ DNS.getDefaultHost(nif) :
+ DNS.getDefaultHost(nif, ns);
+
// get storage info and lock the data dir
storage = new DataStorage( datadir );
// connect to name node