![]() ![]() This command is used to move the file from HDFS to local file system. This command is similar to get command except that destination is restricted to the local file system. Hdfs dfs -get … $> hdfs dfs -get / $> hdfs dfs -copyToLocal / -copyToLocal This command is used to copy files from HDFS to the local file system. Similar to –copyFromLocal command, but it follows cut and paste approach but within a file system $ > hdfs dfs -mv file1.txt /file1.txt -get Hdfs dfs -moveFromLocal $> hdfs dfs -mv / / It ensures that the local copy is deleted. This command will move the file from local file system to HDFS. $> echo "Hello Naveen" | hdfs dfs -put - /file1.txt -moveFromLocal The fundamental difference between -copyFromLocal and -put is the $> hdfs dfs -put file1.txt hdfs://localhost.localdomain:9000/file1.txt -l allows Data Node to lazily persist the file to disk, Forces a replication factor of 1.-d skips creation of temporary file with the suffix.Using -copyFromLocal $ hdfs dfs -copyFromLocal / -put -d : Skip creation of temporary file with the suffix.-p preserves access and modification times, ownership and the permissions.-f overwrites the destination if it already exists.This command is used to copy files from the local file system to the HDFS file system. -ignoreCrc option will disable the checksum verification.This command is used for displaying the contents of a file on the console. In order to overcome that error we will be using -p (parent), which not only ignores if the directory already exists but also create the intermediate directories if they doesn’t exists If the directory already exists or if intermediate directories doesn’t exists then it will throws an error.$ hdfs dfs -mkdir /user/$USER/hdfs_commands Mention not to fail if the directory already exists. Usage : hdfs dfs -mkdir /hdfs-path Options This command is similar to that of Unix mkdir and is used to create a directory in HDFS. -R is used to recursively list the content of the directories.-h is used to print file size in human readable format.-d is used to list the directories as plain files.Usage : hdfs dfs -ls $ hdfs dfs -ls /user/$USERNAME/hdfs_commands This command is used for listing the directories and files present under under a specific directory in an HDFS. List of all HDFS Commands ~]$ hdfs dfs -help Storagepolicies list/get/set block storage policies LsSnapshottableDir list all snapshottable dirs owned by the current user SnapshotDiff diff two snapshots of a directory or diff theĬurrent directory contents with a snapshot Groups get the groups which users belong to Getconf get config values from configuration Oev apply the offline edits viewer to an edits fileįetchdt fetch a delegation token from the NameNode Oiv_legacy apply the offline fsimage viewer to an legacy fsimage ![]() Oiv apply the offline fsimage viewer to an fsimage Mover run a utility to move block replicas across Jmxget get JMX exported values from NameNode or DataNode. Zkfc run the ZK Failover Controller daemonįsck run a DFS filesystem checking utility Secondarynamenode run the DFS secondary namenode Namenode -format format the DFS filesystem Usage: hdfs COMMANDĭfs run a filesystem command on the file systems supported in Hadoop. Most of the commands similar to UNIX file system Desktop]$ hdfs -help.Hadoop provides command line interface to access HDFS. ![]() In this blog post I will explain different HDFS commands to access HDFS which are commonly used while working as a Big Data Developer Training. ![]()
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