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<html><head>
    <title>Hadoop 0.18.0 Release Notes</title></head>
<body>
<font face="sans-serif">
    <h1>Hadoop 0.18.0 Release Notes</h1>

These release notes include new developer and user facing incompatibilities, features, and major improvements.
The table below is sorted by Component.
<ul><a name="changes">
<h2>Changes Since Hadoop 0.17.2</h2>
  <table border="1""100%" cellpadding="4">
   <tbody><tr>
    <td><b>Issue</b></td>
    <td><b>Component</b></td>
    <td><b>Notes</b></td>
   </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3355">HADOOP-3355</a></td>
  <td>conf</td>
  <td>Added support for hexadecimal values in
  Configuration</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-1702">HADOOP-1702</a></td>
  <td>dfs</td>
  <td>Reduced buffer copies as data is written to HDFS.
  The order of sending data bytes and control information has changed, but this
  will not be observed by client applications.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-2065">HADOOP-2065</a></td>
  <td>dfs</td>
  <td>Added &quot;corrupt&quot; flag to LocatedBlock to
  indicate that all replicas of the block thought to be corrupt.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-2585">HADOOP-2585</a></td>
  <td>dfs</td>
  <td>Improved management of replicas of the name space
  image. If all replicas on the Name Node are lost, the latest check point can
  be loaded from the secondary Name Node. Use parameter
  &quot;-importCheckpoint&quot; and specify the location with &quot;fs.checkpoint.dir.&quot;
  The directory structure on the secondary Name Node has changed to match the
  primary Name Node.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-2656">HADOOP-2656</a></td>
  <td>dfs</td>
  <td>Associated a generation stamp with each block. On
  data nodes, the generation stamp is stored as part of the file name of the
  block's meta-data file.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-2703">HADOOP-2703</a></td>
  <td>dfs</td>
  <td>Changed fsck to ignore files opened for writing.
  Introduced new option &quot;-openforwrite&quot; to explicitly show open
  files.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-2797">HADOOP-2797</a></td>
  <td>dfs</td>
  <td>Withdrew the upgrade-to-CRC facility. HDFS will no
  longer support upgrades from versions without CRCs for block data. Users
  upgrading from version 0.13 or earlier must first upgrade to an intermediate
  (0.14, 0.15, 0.16, 0.17) version before doing upgrade to version 0.18 or
  later.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-2865">HADOOP-2865</a></td>
  <td>dfs</td>
  <td>Changed the output of the &quot;fs -ls&quot; command
  to more closely match familiar Linux format. Additional changes were made by
  HADOOP-3459. Applications that parse the command output should be reviewed.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3035">HADOOP-3035</a></td>
  <td>dfs</td>
  <td>Changed protocol for transferring blocks between
  data nodes to report corrupt blocks to data node for re-replication from a
  good replica.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3113">HADOOP-3113</a></td>
  <td>dfs</td>
  <td>Added sync() method to FSDataOutputStream to really,
  really persist data in HDFS. InterDatanodeProtocol to implement this feature.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3164">HADOOP-3164</a></td>
  <td>dfs</td>
  <td>Changed data node to use FileChannel.tranferTo() to
  transfer block data. <br>
  </td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3177">HADOOP-3177</a></td>
  <td>dfs</td>
  <td>Added a new public interface Syncable which declares
  the sync() operation. FSDataOutputStream implements Syncable. If the
  wrappedStream in FSDataOutputStream is Syncalbe, calling
  FSDataOutputStream.sync() is equivalent to call wrappedStream.sync(). Otherwise,
  FSDataOutputStream.sync() is a no-op. Both DistributedFileSystem and
  LocalFileSystem support the sync() operation.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3187">HADOOP-3187</a></td>
  <td>dfs</td>
  <td>Introduced directory quota as hard limits on the
  number of names in the tree rooted at that directory. An administrator may
  set quotas on individual directories explicitly. Newly created directories
  have no associated quota. File/directory creations fault if the quota would
  be exceeded. The attempt to set a quota faults if the directory would be in
  violation of the new quota.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3193">HADOOP-3193</a></td>
  <td>dfs</td>
  <td>Added reporter to FSNamesystem stateChangeLog, and a
  new metric to track the number of corrupted replicas.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3232">HADOOP-3232</a></td>
  <td>dfs</td>
  <td>Changed 'du' command to run in a seperate thread so
  that it does not block user.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3310">HADOOP-3310</a></td>
  <td>dfs</td>
  <td>Implemented Lease Recovery to sync the last bock of
  a file. Added ClientDatanodeProtocol for client trigging block recovery.
  Changed DatanodeProtocol to support block synchronization. Changed
  InterDatanodeProtocol to support block update.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3317">HADOOP-3317</a></td>
  <td>dfs</td>
  <td>Changed the default port for &quot;hdfs:&quot; URIs
  to be 8020, so that one may simply use URIs of the form
  &quot;hdfs://example.com/dir/file&quot;.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3329">HADOOP-3329</a></td>
  <td>dfs</td>
  <td>Changed format of file system image to not store
  locations of last block.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3336">HADOOP-3336</a></td>
  <td>dfs</td>
  <td>Added a log4j appender that emits events from
  FSNamesystem for audit logging</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3339">HADOOP-3339</a></td>
  <td>dfs</td>
  <td>Improved failure handling of last Data Node in write
  pipeline. <br>
  </td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3390">HADOOP-3390</a></td>
  <td>dfs</td>
  <td>Removed deprecated
  ClientProtocol.abandonFileInProgress().</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3452">HADOOP-3452</a></td>
  <td>dfs</td>
  <td>Changed exit status of fsck to report whether the
  files system is healthy or corrupt.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3459">HADOOP-3459</a></td>
  <td>dfs</td>
  <td>Changed the output of the &quot;fs -ls&quot; command
  to more closely match familiar Linux format. Applications that parse the
  command output should be reviewed.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3486">HADOOP-3486</a></td>
  <td>dfs</td>
  <td>Changed the default value of
  dfs.blockreport.initialDelay to be 0 seconds.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3677">HADOOP-3677</a></td>
  <td>dfs</td>
  <td>Simplify generation stamp upgrade by making is a
  local upgrade on datandodes. Deleted distributed upgrade.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-2188">HADOOP-2188</a></td>
  <td>dfs <br>
  ipc</td>
  <td>Replaced timeouts with pings to check that client
  connection is alive. Removed the property ipc.client.timeout from the default
  Hadoop configuration. Removed the metric RpcOpsDiscardedOPsNum. <br>
  </td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3283">HADOOP-3283</a></td>
  <td>dfs <br>
  ipc</td>
  <td>Added an IPC server in DataNode and a new IPC
  protocol InterDatanodeProtocol. Added conf properties
  dfs.datanode.ipc.address and dfs.datanode.handler.count with defaults
  &quot;0.0.0.0:50020&quot; and 3, respectively. <br>
  Changed the serialization in DatanodeRegistration
  and DatanodeInfo, and therefore, updated the versionID in ClientProtocol,
  DatanodeProtocol, NamenodeProtocol.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3058">HADOOP-3058</a></td>
  <td>dfs <br>
  metrics</td>
  <td>Added FSNamesystem status metrics.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3683">HADOOP-3683</a></td>
  <td>dfs <br>
  metrics</td>
  <td>Change FileListed to getNumGetListingOps and add
  CreateFileOps, DeleteFileOps and AddBlockOps metrics.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3265">HADOOP-3265</a></td>
  <td>fs</td>
  <td>Removed deprecated API getFileCacheHints</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3307">HADOOP-3307</a></td>
  <td>fs</td>
  <td>Introduced archive feature to Hadoop. A Map/Reduce
  job can be run to create an archive with indexes. A FileSystem abstraction is
  provided over the archive.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-930">HADOOP-930</a></td>
  <td>fs</td>
  <td>Added support for reading and writing native S3
  files. Native S3 files are referenced using s3n URIs. See
  http://wiki.apache.org/hadoop/AmazonS3 for more details.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3095">HADOOP-3095</a></td>
  <td>fs <br>
  fs/s3</td>
  <td>Added overloaded method
  getFileBlockLocations(FileStatus, long, long). This is an incompatible change
  for FileSystem implementations which override getFileBlockLocations(Path,
  long, long). They should have the signature of this method changed to
  getFileBlockLocations(FileStatus, long, long) to work correctly.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-4">HADOOP-4</a></td>
  <td>fuse-dfs</td>
  <td>Introduced FUSE module for HDFS. Module allows mount
  of HDFS as a Unix filesystem, and optionally the export of that mount point
  to other machines. Writes are disabled. rmdir, mv, mkdir, rm are supported,
  but not cp, touch, and the like. Usage information is attached to the Jira
  record. <br>
  <br>
  </td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3184">HADOOP-3184</a></td>
  <td>hod</td>
  <td>Modified HOD to handle master (NameNode or
  JobTracker) failures on bad nodes by trying to bring them up on another node
  in the ring. Introduced new property ringmaster.max-master-failures to
  specify the maximum number of times a master is allowed to fail.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3266">HADOOP-3266</a></td>
  <td>hod</td>
  <td>Moved HOD change items from CHANGES.txt to a new
  file src/contrib/hod/CHANGES.txt.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3376">HADOOP-3376</a></td>
  <td>hod</td>
  <td>Modified HOD client to look for specific messages
  related to resource limit overruns and take appropriate actions - such as
  either failing to allocate the cluster, or issuing a warning to the user. A
  tool is provided, specific to Maui and Torque, that will set these specific
  messages.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3464">HADOOP-3464</a></td>
  <td>hod</td>
  <td>Implemented a mechanism to transfer HOD errors that
  occur on compute nodes to the submit node running the HOD client, so users
  have good feedback on why an allocation failed.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3483">HADOOP-3483</a></td>
  <td>hod</td>
  <td>Modified HOD to create a cluster directory if one
  does not exist and to auto-deallocate a cluster while reallocating it, if it
  is already dead.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3564">HADOOP-3564</a></td>
  <td>hod</td>
  <td>Modifed HOD to generate the dfs.datanode.ipc.address
  parameter in the hadoop-site.xml of datanodes that it launches.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3610">HADOOP-3610</a></td>
  <td>hod</td>
  <td>Modified HOD to automatically create a cluster
  directory if the one specified with the script command does not exist.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3703">HADOOP-3703</a></td>
  <td>hod</td>
  <td>Modified logcondense.py to use the new format of
  hadoop dfs -lsr output. This version of logcondense would not work with
  previous versions of Hadoop and hence is incompatible.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3061">HADOOP-3061</a></td>
  <td>io</td>
  <td>Introduced ByteWritable and DoubleWritable
  (implementing WritableComparable) implementations for Byte and Double.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3299">HADOOP-3299</a></td>
  <td>io <br>
  mapred</td>
  <td>Changed the TextInputFormat and KeyValueTextInput
  classes to initialize the compressionCodecs member variable before
  dereferencing it.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-2909">HADOOP-2909</a></td>
  <td>ipc</td>
  <td>Removed property ipc.client.maxidletime from the
  default configuration. The allowed idle time is twice
  ipc.client.connection.maxidletime. <br>
  </td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3569">HADOOP-3569</a></td>
  <td>KFS</td>
  <td>Fixed KFS to have read() read and return 1 byte
  instead of 4.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-1915">HADOOP-1915</a></td>
  <td>mapred</td>
  <td>Provided a new method to update counters.
  &quot;incrCounter(String group, String counter, long amount)&quot;</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-2019">HADOOP-2019</a></td>
  <td>mapred</td>
  <td>Added support for .tar, .tgz and .tar.gz files in
  DistributedCache. File sizes are limited to 2GB.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-2095">HADOOP-2095</a></td>
  <td>mapred</td>
  <td>Reduced in-memory copies of keys and values as they
  flow through the Map-Reduce framework. Changed the storage of intermediate
  map outputs to use new IFile instead of SequenceFile for better compression.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-2132">HADOOP-2132</a></td>
  <td>mapred</td>
  <td>Changed &quot;job -kill&quot; to only allow a job
  that is in the RUNNING or PREP state to be killed.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-2181">HADOOP-2181</a></td>
  <td>mapred</td>
  <td>Added logging for input splits in job tracker log
  and job history log. Added web UI for viewing input splits in the job UI and
  history UI.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-236">HADOOP-236</a></td>
  <td>mapred</td>
  <td>Changed connection protocol job tracker and task
  tracker so that task tracker will not connect to a job tracker with a
  different build version.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-2427">HADOOP-2427</a></td>
  <td>mapred</td>
  <td>The current working directory of a task, i.e.
  ${mapred.local.dir}/taskTracker/jobcache/&lt;jobid&gt;/&lt;task_dir&gt;/work
  is cleanedup, as soon as the task is finished.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-2867">HADOOP-2867</a></td>
  <td>mapred</td>
  <td>Added task's cwd to its LD_LIBRARY_PATH.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3135">HADOOP-3135</a></td>
  <td>mapred</td>
  <td>Changed job submission protocol to not allow
  submission if the client's value of mapred.system.dir does not match the job
  tracker's. Deprecated JobConf.getSystemDir(); use JobClient.getSystemDir().</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3221">HADOOP-3221</a></td>
  <td>mapred</td>
  <td>Added org.apache.hadoop.mapred.lib.NLineInputFormat,
  which splits N lines of input as one split. N can be specified by
  configuration property &quot;mapred.line.input.format.linespermap&quot;,
  which defaults to 1.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3226">HADOOP-3226</a></td>
  <td>mapred</td>
  <td>Changed policy for running combiner. The combiner
  may be run multiple times as the map's output is sorted and merged.
  Additionally, it may be run on the reduce side as data is merged. The old
  semantics are available in Hadoop 0.18 if the user calls: <br>
  job.setCombineOnlyOnce(true); <br>
  </td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3326">HADOOP-3326</a></td>
  <td>mapred</td>
  <td>Changed fetchOutputs() so that LocalFSMerger and
  InMemFSMergeThread threads are spawned only once. The thread gets notified
  when something is ready for merge. The merge happens when thresholds are met.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3366">HADOOP-3366</a></td>
  <td>mapred</td>
  <td>Improved shuffle so that all fetched map-outputs are
  kept in-memory before being merged by stalling the shuffle so that the
  in-memory merge executes and frees up memory for the shuffle.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3405">HADOOP-3405</a></td>
  <td>mapred</td>
  <td>Refactored previously public classes MapTaskStatus,
  ReduceTaskStatus, JobSubmissionProtocol, CompletedJobStatusStore to be
  package local.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3417">HADOOP-3417</a></td>
  <td>mapred</td>
  <td>Removed the public class
  org.apache.hadoop.mapred.JobShell. <br>
  Command line options -libjars, -files and -archives are moved to
  GenericCommands. Thus applications have to implement
  org.apache.hadoop.util.Tool to use the options.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3427">HADOOP-3427</a></td>
  <td>mapred</td>
  <td>Changed shuffle scheduler policy to wait for
  notifications from shuffle threads before scheduling more.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3460">HADOOP-3460</a></td>
  <td>mapred</td>
  <td>Created SequenceFileAsBinaryOutputFormat to write
  raw bytes as keys and values to a SequenceFile.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3512">HADOOP-3512</a></td>
  <td>mapred</td>
  <td>Separated Distcp, Logalyzer and Archiver into a
  tools jar.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3565">HADOOP-3565</a></td>
  <td>mapred</td>
  <td>Change the Java serialization framework, which is
  not enabled by default, to correctly make the objects independent of the
  previous objects.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3598">HADOOP-3598</a></td>
  <td>mapred</td>
  <td>Changed Map-Reduce framework to no longer create
  temporary task output directories for staging outputs if staging outputs
  isn't necessary. ${mapred.out.dir}/_temporary/_${taskid}</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-544">HADOOP-544</a></td>
  <td>mapred</td>
  <td>Introduced new classes JobID, TaskID and
  TaskAttemptID, which should be used instead of their string counterparts.
  Deprecated functions in JobClient, TaskReport, RunningJob, jobcontrol.Job and
  TaskCompletionEvent that use string arguments. Applications can use
  xxxID.toString() and xxxID.forName() methods to convert/restore objects
  to/from strings. <br>
  </td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3230">HADOOP-3230</a></td>
  <td>scripts</td>
  <td>Added command line tool &quot;job -counter
  &lt;job-id&gt; &lt;group-name&gt; &lt;counter-name&gt;&quot; to access
  counters.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-1328">HADOOP-1328</a></td>
  <td>streaming</td>
  <td>Introduced a way for a streaming process to update
  global counters and status using stderr stream to emit information. Use
  &quot;reporter:counter:&lt;group&gt;,&lt;counter&gt;,&lt;amount&gt; &quot; to
  update a counter. Use &quot;reporter:status:&lt;message&gt;&quot; to update
  status.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3429">HADOOP-3429</a></td>
  <td>streaming</td>
  <td>Increased the size of the buffer used in the
  communication between the Java task and the Streaming process to 128KB.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3379">HADOOP-3379</a></td>
  <td>streaming <br>
  documentation</td>
  <td>Set default value for configuration property
  &quot;stream.non.zero.exit.status.is.failure&quot; to be &quot;true&quot;.</td>
 </tr>
 <tr>
  <td><a
  href="https://issues.apache.org/jira/browse/HADOOP-3246">HADOOP-3246</a></td>
  <td>util</td>
  <td>Introduced an FTPFileSystem backed by Apache Commons
  FTPClient to directly store data into HDFS.</td>
 </tr>
</tbody></table>
</ul>
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