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03:49:20&quot;,&quot;http_code&quot;:403},&quot;process&quot;:&quot;done&quot;},{&quot;id&quot;:2260,&quot;href&quot;:&quot;http:\\\/\\\/data-flair.training\\\/forums\\\/topic\\\/how-does-hdfs-ensure-data-integrity-of-data-blocks-stored-in-hdfs&quot;,&quot;archived_href&quot;:&quot;http:\\\/\\\/web-wp.archive.org\\\/web\\\/20200923032036\\\/https:\\\/\\\/data-flair.training\\\/forums\\\/topic\\\/how-does-hdfs-ensure-data-integrity-of-data-blocks-stored-in-hdfs\\\/&quot;,&quot;redirect_href&quot;:&quot;&quot;,&quot;checks&quot;:[{&quot;date&quot;:&quot;2025-12-11 03:49:23&quot;,&quot;http_code&quot;:403}],&quot;broken&quot;:false,&quot;last_checked&quot;:{&quot;date&quot;:&quot;2025-12-11 03:49:23&quot;,&quot;http_code&quot;:403},&quot;process&quot;:&quot;done&quot;},{&quot;id&quot;:2261,&quot;href&quot;:&quot;http:\\\/\\\/data-flair.training\\\/forums\\\/topic\\\/why-slaves-limited-to-4000-in-hadoop-version-1&quot;,&quot;archived_href&quot;:&quot;http:\\\/\\\/web-wp.archive.org\\\/web\\\/20181101061234\\\/http:\\\/\\\/data-flair.training:80\\\/forums\\\/topic\\\/why-slaves-limited-to-4000-in-hadoop-version-1&quot;,&quot;redirect_href&quot;:&quot;&quot;,&quot;checks&quot;:[{&quot;date&quot;:&quot;2025-12-11 03:49:26&quot;,&quot;http_code&quot;:403}],&quot;broken&quot;:true,&quot;last_checked&quot;:{&quot;date&quot;:&quot;2025-12-11 03:49:26&quot;,&quot;http_code&quot;:403},&quot;process&quot;:&quot;done&quot;}]'><\/div>\n<h1>Hadoop HDFS Interview Questions and Answers: Objective<\/h1>\n<p><strong><a href=\"http:\/\/data-flair.training\/blogs\/hadoop-introduction-tutorial-quick-guide\/\">Hadoop<\/a> <\/strong>distributed file system<strong> (HDFS)<\/strong> is a system that stores very large dataset. As it is the most important component of <a href=\"http:\/\/data-flair.training\/blogs\/hadoop-hdfs-architecture\/\"><strong>Hadoop Architecture<\/strong><\/a> so it is the most important topic for an interview. In this blog, we provide the 50+ Hadoop HDFS interview questions and answers that are being framed by our company expert who provides training in <strong>Hadoop<\/strong> and another Bigdata framework. A Proper care has been taken while answering these questions. So we can provide you the best question and their answer. Hope these question will help you to crack Hadoop interview. All the best!!!!!!!<\/p>\n<div id=\"attachment_42487\" style=\"width: 1210px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2017\/07\/50-hdfs-interview-questions-and-answers-2.jpg\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-42487\" class=\"size-full wp-image-42487\" src=\"https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2017\/07\/50-hdfs-interview-questions-and-answers-2.jpg\" alt=\"Top 50+ Hadoop HDFS Interview Questions and Answers\" width=\"1200\" height=\"628\" srcset=\"https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2017\/07\/50-hdfs-interview-questions-and-answers-2.jpg 1200w, https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2017\/07\/50-hdfs-interview-questions-and-answers-2-150x79.jpg 150w, https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2017\/07\/50-hdfs-interview-questions-and-answers-2-300x157.jpg 300w, https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2017\/07\/50-hdfs-interview-questions-and-answers-2-768x402.jpg 768w, https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2017\/07\/50-hdfs-interview-questions-and-answers-2-1024x536.jpg 1024w, https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2017\/07\/50-hdfs-interview-questions-and-answers-2-520x272.jpg 520w\" sizes=\"auto, (max-width: 1200px) 100vw, 1200px\" \/><\/a><p id=\"caption-attachment-42487\" class=\"wp-caption-text\">Top 50+ Hadoop HDFS Interview Questions and Answers<\/p><\/div>\n<p><strong style=\"font-size: 20px !important\">50+ Best Hadoop HDFS Interview Questions And Answers<\/strong><br \/>\n<strong>1) What is Hadoop?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/what-is-apache-hadoop\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>2) What is Hadoop Distributed File System- HDFS?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/what-is-hdfs-hadoop-distributed-file-system\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>3) What is NameNode and DataNode in HDFS?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/explain-namenode-and-datanode-in-hdfs\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>4) How NameNode tackle Datanode failures in HDFS? <\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/how-namenode-tackle-datanode-failures-in-hadoop\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>5) What do you mean by metadata in Hadoop?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/what-do-you-mean-by-metadata-in-hdfs\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>6) In which location NameNode stores its Metadata? And why? <\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/in-which-location-namenode-stores-its-metadata-and-why\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>7) How much Metadata will be created on NameNode in Hadoop?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/how-much-metadata-will-be-created-on-namenode\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>8) When NameNode enter in Safe Mode?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/when-hadoop-enter-in-safe-mode\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>9) How to restart NameNode or all the daemons in Hadoop HDFS?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/how-to-restart-namenode-or-all-the-daemons-in-hadoop\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>10) What are the modes in which Apache Hadoop run? <\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/what-are-the-modes-in-which-hadoop-run\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>11) On what basis name node distribute blocks across the data nodes in HDFS? <\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/on-what-basis-name-node-distribute-blocks-across-the-data-nodes\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>12) What is a block in HDFS, why block size 64MB? <\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/data-node-block-size-in-hdfs-why-64mb\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>13) Why is block size large in Hadoop? <\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/why-hdfs-block-size-is-large\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>14) What is Fault Tolerance in Hadoop HDFS?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/what-is-fault-tolerance-in-hdfs\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>15) Why is block size set to 128 MB in HDFS?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/why-block-size-is-set-to-128-mb-in-hadoop\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\nAny doubt in the Hadoop HDFS interview questions and answers yet? Feel free to ask in the comment section below anytime and out support team will get back to you.<br \/>\n<strong>16) What happens if the block on Hadoop HDFS is corrupted?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/what-happens-if-the-block-on-hdfs-is-corrupted\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>17) What is the difference between NameNode and DataNode in Hadoop?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/difference-between-namenode-and-datanode-in-hadoop\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>18) How data or file is read in Hadoop HDFS?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/how-data-or-file-is-read-in-hdfs\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>19) How data or file is written into Hadoop HDFS?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/how-data-or-file-is-written-into-hdfs\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>20) Ideally what should be the block size in Hadoop?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/ideally-what-should-be-the-block-size-in-hadoop-cluster\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>21) What is Heartbeat in Hadoop?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/heartbeat-for-hadoop\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>22) How often DataNode send heartbeat to NameNode in Hadoop?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/how-often-datanode-send-heartbeat-to-namenode\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>23) While starting Hadoop services, DataNode service is not running?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/while-starting-hadoop-services-datanode-service-is-not-running\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>24) How HDFS helps NameNode in scaling in Hadoop?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/how-hdfs-helps-namenode-in-scaling\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>25) What is Secondary NameNode in Hadoop HDFS? <\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/what-is-secondary-namenode-in-hadoop\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>26) Ideally what should be the replication factor in Hadoop?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/ideally-what-should-be-the-replication-factor-in-hadoop-cluster\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>27) How one can change Replication factor when Data is already stored in HDFS<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/how-we-can-change-replication-factor-when-data-is-already-stored-in-hdfs\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>28) Why HDFS performs replication, although it results in data redundancy in Hadoop?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/why-hdfs-performs-replication-although-it-results-in-data-redundancy\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>29) What is Safemode in Apache Hadoop?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/what-is-safemode-in-hadoop\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>30) What happen when namenode enters in safemode in hadoop?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/what-name-node-does-when-it-enters-in-safemode\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\nIf at any point you don&#8217;t understand Hadoop HDFS Interview Questions and Answers feel free to ask us in the comment sections. We will be glad to help you with the Hadoop HDFS Interview Questions and Answers problems.<br \/>\n<strong>31) How to remove safemode of namenode forcefully in HDFS?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/how-to-remove-safemode-of-namenode-forcefully\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>32) How to create the directory when Name node is in safe mode?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/mkdir-cannot-create-directory-data-name-node-is-in-safe-mode\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>33) Why can we not\u00a0create directory \/user\/dataflair\/inpdata001 when Name node is in safe mode?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/cannot-create-directory-userdataflairinpdata001-name-node-is-in-safe-mode\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>34) What is difference between a MapReduce InputSplit and HDFS block <\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/what-is-the-fundamental-difference-between-a-mapreduce-inputsplit-and-hdfs-block\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>35) Explain Small File Problem in Hadoop <\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/small-file-problem-in-hadoop\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>36) What is the difference between HDFS and NAS?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/what-is-difference-between-nas-and-hdfs\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>37) How to create Users in hadoop HDFS?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/httpdata-flaircomanswershow-to-create-users-in-hdfs\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>38) What Happens When NameNode Goes down during File Read Operation in Hadoop?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/what-happens-when-namenode-goes-down-during-file-read-operation\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>39) Explain HDFS \u201cWrite once Read many\u201d pattern<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/hdfs-follow-%e2%80%9cwrite-once-read-many%e2%80%9d-pattern\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>39) Can multiple clients write into an HDFS file concurrently in hadoop?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/can-multiple-clients-write-into-an-hdfs-file-concurrently\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>40) Does HDFS allow a client to read a file which is already opened for writing in hadoop? <\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/does-hdfs-allow-a-client-to-read-a-file-which-is-already-opened-for-writing\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>41) What should be the HDFS Block size to get maximum performance from Hadoop cluster? <\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/what-should-be-the-block-size-to-get-maximum-performance-from-hadoop-cluster\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>42) Why HDFS stores data using commodity hardware despite the higher chance of failures in hadoop?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/why-hdfs-stores-data-using-commodity-hardware-despite-higher-chance-of-failures\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>43) Who divides the file into Block while storing inside hdfs in hadoop?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/who-divide-the-file-into-block-while-storing-inside-hdfs\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>44) What is active and passive NameNode in HDFS?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/what-is-active-and-passive-namenode-in-hadoop\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>45) How is indexing done in hadoop HDFS?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/how-indexing-is-done-in-hdfs\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>46) What is rack awareness in Hadoop?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/what-is-rack-awareness-in-hadoop-hdfs\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>47) What is Erasure Coding in Hadoop?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/explain-erasure-coding-in-hadoop\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>48) When and how to create hadoop archive?<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/when-and-how-to-create-hadoop-archive\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>49) What is non-dfs used in HDFS web console<\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/what-is-non-dfs-used-in-hdfs-web-console\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>50) How does HDFS ensure Data Integrity of data blocks stored in Hadoop HDFS? <\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/how-does-hdfs-ensure-data-integrity-of-data-blocks-stored-in-hdfs\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\n<strong>51) Why slaves limited to 4000 in Hadoop Version1? <\/strong><br \/>\n<strong><a href=\"http:\/\/data-flair.training\/forums\/topic\/why-slaves-limited-to-4000-in-hadoop-version-1\" target=\"_blank\" rel=\"noopener noreferrer\">View Answer &gt;&gt;<\/a><\/strong><br \/>\nIf in case you feel any query in Hadoop HDFS interview questions and answers, leave a comment in a section given below.<br \/>\n<strong>See Also-<\/strong><\/p>\n<ul>\n<li><a href=\"http:\/\/data-flair.training\/blogs\/top-100-hadoop-interview-questions-and-answers\/\">100 Hadoop Interview Questions and Answers<\/a><\/li>\n<li><a href=\"http:\/\/data-flair.training\/blogs\/mapreduce-interview-questions\/\">50+ MapReduce Interview Questions<\/a><\/li>\n<li><a href=\"https:\/\/data-flair.training\/blogs\/hdfs-interview-questions-and-answers\/\">Hadoop HDFS Interview Questions and Answers<\/a><\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Hadoop HDFS Interview Questions and Answers: Objective Hadoop distributed file system (HDFS) is a system that stores very large dataset. As it is the most important component of Hadoop Architecture so it is the&#46;&#46;&#46;<\/p>\n","protected":false},"author":7,"featured_media":42487,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[25],"tags":[782,5256,5259,5283,5562,5574,5580],"class_list":["post-3085","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-hdfs","tag-apache-hadoop","tag-hadoop-hdfs","tag-hadoop-hdfs-interview-questions","tag-hadoop-mapreduce","tag-hdfs-datanodes","tag-hdfs-interview-questions","tag-hdfs-name-node"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.4 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Top 50+ Hadoop HDFS Interview Questions and Answers - DataFlair<\/title>\n<meta name=\"description\" content=\"Best 50+ HDFS Interview Questions and answers to crack Hadoop Interview covers all the Questions of Apache Hadoop HDFS with detailed answers for Hadoop Jobs\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/data-flair.training\/blogs\/top-hdfs-interview-questions-and-answers\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Top 50+ Hadoop HDFS Interview Questions and Answers - 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