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<h1>Hadoop Shell Commands</h1>
<div id="minitoc-area">
<ul class="minitoc">
<li>
<a href="#DFShell"> DFShell </a>
</li>
<li>
<a href="#cat"> cat </a>
</li>
<li>
<a href="#chgrp"> chgrp </a>
</li>
<li>
<a href="#chmod"> chmod </a>
</li>
<li>
<a href="#chown"> chown </a>
</li>
<li>
<a href="#copyFromLocal">copyFromLocal</a>
</li>
<li>
<a href="#copyToLocal"> copyToLocal</a>
</li>
<li>
<a href="#cp"> cp </a>
</li>
<li>
<a href="#du">du</a>
</li>
<li>
<a href="#dus"> dus </a>
</li>
<li>
<a href="#expunge"> expunge </a>
</li>
<li>
<a href="#get"> get </a>
</li>
<li>
<a href="#getmerge"> getmerge </a>
</li>
<li>
<a href="#ls"> ls </a>
</li>
<li>
<a href="#lsr">lsr</a>
</li>
<li>
<a href="#mkdir"> mkdir </a>
</li>
<li>
<a href="#movefromLocal"> movefromLocal </a>
</li>
<li>
<a href="#mv"> mv </a>
</li>
<li>
<a href="#put"> put </a>
</li>
<li>
<a href="#rm"> rm </a>
</li>
<li>
<a href="#rmr"> rmr </a>
</li>
<li>
<a href="#setrep"> setrep </a>
</li>
<li>
<a href="#stat"> stat </a>
</li>
<li>
<a href="#tail"> tail </a>
</li>
<li>
<a href="#test"> test </a>
</li>
<li>
<a href="#text"> text </a>
</li>
<li>
<a href="#touchz"> touchz </a>
</li>
</ul>
</div>
<a name="N1000D"></a><a name="DFShell"></a>
<h2 class="h3"> DFShell </h2>
<div class="section">
<p>
The HDFS shell is invoked by
<span class="codefrag">bin/hadoop dfs &lt;args&gt;</span>.
All the HDFS shell commands take path URIs as arguments. The URI format is <em>scheme://autority/path</em>. For HDFS the scheme is <em>hdfs</em>, and for the local filesystem the scheme is <em>file</em>. The scheme and authority are optional. If not specified, the default scheme specified in the configuration is used. An HDFS file or directory such as <em>/parent/child</em> can be specified as <em>hdfs://namenode:namenodeport/parent/child</em> or simply as <em>/parent/child</em> (given that your configuration is set to point to <em>namenode:namenodeport</em>). Most of the commands in HDFS shell behave like corresponding Unix commands. Differences are described with each of the commands. Error information is sent to <em>stderr</em> and the output is sent to <em>stdout</em>.
</p>
</div>
<a name="N10035"></a><a name="cat"></a>
<h2 class="h3"> cat </h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -cat URI [URI &hellip;]</span>
</p>
<p>
Copies source paths to <em>stdout</em>.
</p>
<p>Example:</p>
<ul>
<li>
<span class="codefrag"> hadoop dfs -cat hdfs://host1:port1/file1 hdfs://host2:port2/file2
</span>
</li>
<li>
<span class="codefrag">hadoop dfs -cat file:///file3 /user/hadoop/file4 </span>
</li>
</ul>
<p>Exit Code:<br>
<span class="codefrag"> Returns 0 on success and -1 on error. </span>
</p>
</div>
<a name="N10061"></a><a name="chgrp"></a>
<h2 class="h3"> chgrp </h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -chgrp [-R] GROUP URI [URI &hellip;]</span>
</p>
<p>
Change group association of files. With <span class="codefrag">-R</span>, make the change recursively through the directory structure. The user must be the owner of files, or else a super-user. Additional information is in the <a href="hdfs_permissions_guide.html">Permissions User Guide</a>.
</p>
</div>
<a name="N10078"></a><a name="chmod"></a>
<h2 class="h3"> chmod </h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -chmod [-R] &lt;MODE[,MODE]... | OCTALMODE&gt; URI [URI &hellip;]</span>
</p>
<p>
Change the permissions of files. With <span class="codefrag">-R</span>, make the change recursively through the directory structure. The user must be the owner of the file, or else a super-user. Additional information is in the <a href="hdfs_permissions_guide.html">Permissions User Guide</a>.
</p>
</div>
<a name="N1008F"></a><a name="chown"></a>
<h2 class="h3"> chown </h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -chown [-R] [OWNER][:[GROUP]] URI [URI ]</span>
</p>
<p>
Change the owner of files. With <span class="codefrag">-R</span>, make the change recursively through the directory structure. The user must be a super-user. Additional information is in the <a href="hdfs_permissions_guide.html">Permissions User Guide</a>.
</p>
</div>
<a name="N100A6"></a><a name="copyFromLocal"></a>
<h2 class="h3">copyFromLocal</h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -copyFromLocal &lt;localsrc&gt; URI</span>
</p>
<p>Similar to <a href="#putlink"><strong>put</strong></a> command, except that the source is restricted to a local file reference. </p>
</div>
<a name="N100BB"></a><a name="copyToLocal"></a>
<h2 class="h3"> copyToLocal</h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -copyToLocal [-ignorecrc] [-crc] URI &lt;localdst&gt;</span>
</p>
<p> Similar to <a href="#getlink"><strong>get</strong></a> command, except that the destination is restricted to a local file reference.</p>
</div>
<a name="N100D0"></a><a name="cp"></a>
<h2 class="h3"> cp </h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -cp URI [URI &hellip;] &lt;dest&gt;</span>
</p>
<p>
Copy files from source to destination. This command allows multiple sources as well in which case the destination must be a directory.
<br>
Example:</p>
<ul>
<li>
<span class="codefrag"> hadoop dfs -cp /user/hadoop/file1 /user/hadoop/file2</span>
</li>
<li>
<span class="codefrag"> hadoop dfs -cp /user/hadoop/file1 /user/hadoop/file2 /user/hadoop/dir </span>
</li>
</ul>
<p>Exit Code:</p>
<p>
<span class="codefrag"> Returns 0 on success and -1 on error.</span>
</p>
</div>
<a name="N100FA"></a><a name="du"></a>
<h2 class="h3">du</h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -du URI [URI &hellip;]</span>
</p>
<p>
Displays aggregate length of files contained in the directory or the length of a file in case its just a file.<br>
Example:<br>
<span class="codefrag">hadoop dfs -du /user/hadoop/dir1 /user/hadoop/file1 hdfs://host:port/user/hadoop/dir1</span>
<br>
Exit Code:<br>
<span class="codefrag"> Returns 0 on success and -1 on error. </span>
<br>
</p>
</div>
<a name="N10115"></a><a name="dus"></a>
<h2 class="h3"> dus </h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -dus &lt;args&gt;</span>
</p>
<p>
Displays a summary of file lengths.
</p>
</div>
<a name="N10125"></a><a name="expunge"></a>
<h2 class="h3"> expunge </h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -expunge</span>
</p>
<p>Empty the Trash. Refer to <a href="hdfs_design.html">HDFS Design</a> for more information on Trash feature.
</p>
</div>
<a name="N10139"></a><a name="get"></a>
<h2 class="h3"> get </h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -get [-ignorecrc] [-crc] &lt;src&gt; &lt;localdst&gt;</span>
<br>
</p>
<p>
Copy files to the local file system. Files that fail the CRC check may be copied with the
<span class="codefrag">-ignorecrc</span> option. Files and CRCs may be copied using the
<span class="codefrag">-crc</span> option.
</p>
<p>Example:</p>
<ul>
<li>
<span class="codefrag"> hadoop dfs -get /user/hadoop/file localfile </span>
</li>
<li>
<span class="codefrag"> hadoop dfs -get hdfs://host:port/user/hadoop/file localfile</span>
</li>
</ul>
<p>Exit Code:</p>
<p>
<span class="codefrag"> Returns 0 on success and -1 on error. </span>
</p>
</div>
<a name="N1016D"></a><a name="getmerge"></a>
<h2 class="h3"> getmerge </h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -getmerge &lt;src&gt; &lt;localdst&gt; [addnl]</span>
</p>
<p>
Takes a source directory and a destination file as input and concatenates files in src into the destination local file. Optionally <span class="codefrag">addnl</span> can be set to enable adding a newline character at the end of each file.
</p>
</div>
<a name="N10180"></a><a name="ls"></a>
<h2 class="h3"> ls </h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -ls &lt;args&gt;</span>
</p>
<p>
For a file returns stat on the file with the following format:<br>
<span class="codefrag">filename &lt;number of replicas&gt; filesize modification_date modification_time permissions userid groupid</span>
<br>
For a directory it returns list of its direct children as in unix.
A directory is listed as: <br>
<span class="codefrag">dirname &lt;dir&gt; modification_time modification_time permissions userid groupid</span>
<br>
Example:<br>
<span class="codefrag">hadoop dfs -ls /user/hadoop/file1 /user/hadoop/file2 hdfs://host:port/user/hadoop/dir1 /nonexistentfile</span>
<br>
Exit Code:<br>
<span class="codefrag"> Returns 0 on success and -1 on error. </span>
<br>
</p>
</div>
<a name="N101A3"></a><a name="lsr"></a>
<h2 class="h3">lsr</h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -lsr &lt;args&gt;</span>
<br>
Recursive version of <span class="codefrag">ls</span>. Similar to Unix <span class="codefrag">ls -R</span>.
</p>
</div>
<a name="N101B6"></a><a name="mkdir"></a>
<h2 class="h3"> mkdir </h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -mkdir &lt;paths&gt;</span>
<br>
</p>
<p>
Takes path uri's as argument and creates directories. The behavior is much like unix mkdir -p creating parent directories along the path.
</p>
<p>Example:</p>
<ul>
<li>
<span class="codefrag">hadoop dfs -mkdir /user/hadoop/dir1 /user/hadoop/dir2 </span>
</li>
<li>
<span class="codefrag">hadoop dfs -mkdir hdfs://host1:port1/user/hadoop/dir hdfs://host2:port2/user/hadoop/dir
</span>
</li>
</ul>
<p>Exit Code:</p>
<p>
<span class="codefrag">Returns 0 on success and -1 on error.</span>
</p>
</div>
<a name="N101E3"></a><a name="movefromLocal"></a>
<h2 class="h3"> movefromLocal </h2>
<div class="section">
<p>
<span class="codefrag">Usage: dfs -moveFromLocal &lt;src&gt; &lt;dst&gt;</span>
</p>
<p>Displays a "not implemented" message.
</p>
</div>
<a name="N101F3"></a><a name="mv"></a>
<h2 class="h3"> mv </h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -mv URI [URI &hellip;] &lt;dest&gt;</span>
</p>
<p>
Moves files from source to destination. This command allows multiple sources as well in which case the destination needs to be a directory. Moving files across filesystems is not permitted.
<br>
Example:
</p>
<ul>
<li>
<span class="codefrag"> hadoop dfs -mv /user/hadoop/file1 /user/hadoop/file2</span>
</li>
<li>
<span class="codefrag"> hadoop dfs -mv hdfs://host:port/file1 hdfs://host:port/file2 hdfs://host:port/file3 hdfs://host:port/dir1</span>
</li>
</ul>
<p>Exit Code:</p>
<p>
<span class="codefrag"> Returns 0 on success and -1 on error.</span>
</p>
</div>
<a name="N1021D"></a><a name="put"></a>
<h2 class="h3"> put </h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -put &lt;localsrc&gt; ... &lt;dst&gt;</span>
</p>
<p>Copy single src, or multiple srcs from local file system to the destination filesystem. Also reads input from stdin and writes to destination filesystem.<br>
</p>
<ul>
<li>
<span class="codefrag"> hadoop dfs -put localfile /user/hadoop/hadoopfile</span>
</li>
<li>
<span class="codefrag"> hadoop dfs -put localfile1 localfile2 /user/hadoop/hadoopdir</span>
</li>
<li>
<span class="codefrag"> hadoop dfs -put localfile hdfs://host:port/hadoop/hadoopfile</span>
</li>
<li>
<span class="codefrag">hadoop dfs -put - hdfs://host:port/hadoop/hadoopfile</span>
<br>Reads the input from stdin.</li>
</ul>
<p>Exit Code:</p>
<p>
<span class="codefrag"> Returns 0 on success and -1 on error. </span>
</p>
</div>
<a name="N10254"></a><a name="rm"></a>
<h2 class="h3"> rm </h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -rm URI [URI &hellip;] </span>
</p>
<p>
Delete files specified as args. Only deletes non empty directory and files. Refer to rmr for recursive deletes.<br>
Example:
</p>
<ul>
<li>
<span class="codefrag"> hadoop dfs -rm hdfs://host:port/file /user/hadoop/emptydir </span>
</li>
</ul>
<p>Exit Code:</p>
<p>
<span class="codefrag"> Returns 0 on success and -1 on error.</span>
</p>
</div>
<a name="N10278"></a><a name="rmr"></a>
<h2 class="h3"> rmr </h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -rmr URI [URI &hellip;]</span>
</p>
<p>Recursive version of delete.<br>
Example:
</p>
<ul>
<li>
<span class="codefrag"> hadoop dfs -rmr /user/hadoop/dir </span>
</li>
<li>
<span class="codefrag"> hadoop dfs -rmr hdfs://host:port/user/hadoop/dir </span>
</li>
</ul>
<p>Exit Code:</p>
<p>
<span class="codefrag"> Returns 0 on success and -1 on error. </span>
</p>
</div>
<a name="N102A2"></a><a name="setrep"></a>
<h2 class="h3"> setrep </h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -setrep [-R] &lt;path&gt;</span>
</p>
<p>
Changes the replication factor of a file. -R option is for recursively increasing the replication factor of files within a directory.
</p>
<p>Example:</p>
<ul>
<li>
<span class="codefrag"> hadoop dfs -setrep -w 3 -R /user/hadoop/dir1 </span>
</li>
</ul>
<p>Exit Code:</p>
<p>
<span class="codefrag">Returns 0 on success and -1 on error. </span>
</p>
</div>
<a name="N102C7"></a><a name="stat"></a>
<h2 class="h3"> stat </h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -stat URI [URI &hellip;]</span>
</p>
<p>
Returns the stat information on the path.
</p>
<p>Example:</p>
<ul>
<li>
<span class="codefrag"> hadoop dfs -stat path </span>
</li>
</ul>
<p>Exit Code:<br>
<span class="codefrag"> Returns 0 on success and -1 on error.</span>
</p>
</div>
<a name="N102EA"></a><a name="tail"></a>
<h2 class="h3"> tail </h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -tail [-f] URI </span>
</p>
<p>
Displays last kilobyte of the file to stdout. -f option can be used as in Unix.
</p>
<p>Example:</p>
<ul>
<li>
<span class="codefrag"> hadoop dfs -tail pathname </span>
</li>
</ul>
<p>Exit Code: <br>
<span class="codefrag"> Returns 0 on success and -1 on error.</span>
</p>
</div>
<a name="N1030D"></a><a name="test"></a>
<h2 class="h3"> test </h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -test -[ezd] URI</span>
</p>
<p>
Options: <br>
-e check to see if the file exists. Return 0 if true. <br>
-z check to see if the file is zero length. Return 0 if true <br>
-d check return 1 if the path is directory else return 0. <br>
</p>
<p>Example:</p>
<ul>
<li>
<span class="codefrag"> hadoop dfs -test -e filename </span>
</li>
</ul>
</div>
<a name="N10330"></a><a name="text"></a>
<h2 class="h3"> text </h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -text &lt;src&gt;</span>
<br>
</p>
<p>
Takes a source file and outputs the file in text format. The allowed formats are zip and TextRecordInputStream.
</p>
</div>
<a name="N10342"></a><a name="touchz"></a>
<h2 class="h3"> touchz </h2>
<div class="section">
<p>
<span class="codefrag">Usage: hadoop dfs -touchz URI [URI &hellip;]</span>
<br>
</p>
<p>
Create a file of zero length.
</p>
<p>Example:</p>
<ul>
<li>
<span class="codefrag"> hadoop -touchz pathname </span>
</li>
</ul>
<p>Exit Code:<br>
<span class="codefrag"> Returns 0 on success and -1 on error.</span>
</p>
</div>
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