tag:blogger.com,1999:blog-19267307578081903152024-09-13T13:04:31.537+05:30Rajeswara ReddyRajeswara Reddyhttp://www.blogger.com/profile/00310938672011421370noreply@blogger.comBlogger1125tag:blogger.com,1999:blog-1926730757808190315.post-30227137412013945872016-01-18T13:41:00.003+05:302017-07-27T11:54:20.016+05:30Hadoop Overview<div dir="ltr" style="text-align: left;" trbidi="on">
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<br class="Apple-interchange-newline" />Hadoop Overview</h2>
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<span style="font-family: "verdana" , sans-serif; font-size: xx-small;">Hadoop File System was developed using distributed file system design. It is run on commodity hardware. Unlike other distributed systems, HDFS is highly fault tolerant and designed using low-cost hardware. </span></div>
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<span style="font-family: "verdana" , sans-serif;"><span style="font-family: "verdana" , sans-serif; font-size: xx-small;"> HDFS holds very large amount of data and provides easier access. To store such huge data, the files are stored across multiple machines. These files are stored in redundant fashion to rescue the system from possible data losses in case of failure. HDFS also makes applications available to parallel processing.</span></span></div>
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<span style="font-family: "verdana" , sans-serif;">The important features of HDFS are </span></div>
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<li><span style="font-family: "verdana" , sans-serif;">HDFS is mainly suited for distributed storage and processing of the data.</span></li>
<li><span style="font-family: "verdana" , sans-serif;">Streaming access to file system data.</span></li>
<li><span style="font-family: "verdana" , sans-serif;">HDFS follows master-slave architecture</span></li>
<li><span style="font-family: "verdana" , sans-serif;">Namenode and Datanode help users to easily check the heartbeat of the nodes in the cluster</span></li>
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<span style="line-height: 24px;"><span style="font-family: "verdana" , sans-serif;">Namenode:</span></span><br />
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<li>Manages the file system namespace.</li>
<li>Regulates client’s access to files.</li>
<li>It also executes file system operations such as renaming, closing, and opening files and directories.</li>
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</span></span><span style="font-family: "verdana" , sans-serif;"><span style="font-family: "verdana" , sans-serif;"><span style="line-height: 24px;">Datanode:</span></span></span><br />
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<span style="font-family: "verdana" , sans-serif;">Following are the tasks of Datanode</span><br />
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<li>Datanode performs read/write operations</li>
<li>perform operations such as block creation, deletion and replication</li>
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<span style="font-family: "verdana" , sans-serif; font-size: xx-small;">Namenode is a software that runs on commodity hardware which acts as master server across the cluster</span><br />
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<span style="font-family: "verdana" , sans-serif; font-size: xx-small;">Following are the tasks of namenode</span></div>
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<span style="font-family: "verdana" , sans-serif; font-size: xx-small;"><span style="font-family: "verdana" , sans-serif; line-height: 24px;">The Datanode is a software that runs on commodity hardware, system which has datanode acts as slave across the cluster</span></span></div>
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Rajeswara Reddyhttp://www.blogger.com/profile/00310938672011421370noreply@blogger.com