Hi Guest 1 HomePage 1 Jobs 1 WalkIn 1Articles  

 :) Latest Topic
Used Cars
New Bikes
Used Bikes
Commercial Vehicels
Car Dealer
Bike Dealer
SQL Query
 New Cars
 :) Hot Jobs
 :) Latest Articles


Hadoop different Commands used in HDFS
Question Posted on 02 Oct 2019

Home >> BigData >> Hadoop >> Hadoop different Commands used in HDFS

Hadoop different Commands used in HDFS
Below are the different commands which is used in Hadoop. Before this i have mention the different syntax used in below commands.
"< path>" This mean file or directory name.
"< path>..." This means 1 or more file or directory names.
"< file>" This means any filename.
"< src>" and "< dest>" These are path names in a directed operation.
"< localSrc>" and "< localDest>" These are paths as above placed on the local file system.
Now the list of commands

(1)-ls < path>:-Lists the contents of the directory specified by path and shows the names, permissions, owner, size and modification date for each entry placed in the path.

(2)-lsr < path>:-This is same as -ls but r will helps in recursively displays entries in all subdirectories of path.

(3)-du < path>:-This will shows Shows disk usage, in bytes, for all the files given in the match path. And filenames are reported with the full HDFS protocol prefix.

(4)-dus < path>:-It is same as -du but will prints summary of dis usage of all files directories in the given path.

(5)-mv < src>< dest>:-This command will moves the file or directory from defined src to dest in HDFS.

(6)-cp < src>< dest>:-This will copies the files or directory with given src to dest in HDFS.

(7)-rm < path>:-This command will Removes the file or empty directory at given path.

(8)-rmr < path>:-This will do the same as above command but will delete files rom subdirectory too.

(9)-put < localSrc> < dest>:-This will copies the files or directory from local file system which is define in localSrc to dest in HDFS.

(10)-copyFromLocal < localSrc> < dest>:-This is same as -put

(11)-moveFromLocal < localSrc> < dest>:-This will copies the files or directory from local file system which is define in localSrc to dest in HDFS in addition will deletes the local copy on success.

(12)-get [-crc] < src> < localDest>:-This will copies the file or directory in HDFS identified by src to the local file system path identified by localDest.

(13)-getmerge < src> < localDest>:-This will retrieves all files that match the path src in HDFS, and copies them to a single, merged file in the local file system identified by localDest.

(14)-cat < filen-ame>:-This will display the contents of filename on stdout.

(15)-copyToLocal < src> < localDest>:-This is same as command no 12.

(16)-moveToLocal < src> < localDest>:-This will do the same as -get but will deletes the HDFS copy on success.

(17)-mkdir < path>:-This will creates directory named path in HDFS.

(18)-setrep [-R] [-w] rep < path>:-This will sets the target replication factor for files identified by the path to rep.

(19)-touchz < path>:-This will creates a file at path containing the current time as a timestamp. Fails if a file already exists at path, unless the file is already size 0.

(20)-test -[ezd] < path>:-This will used to chec the path exists or not if returns 1 if it is exists. If this have zero length or is a directory. 0 otherwise.

(21)-stat[format]< path>:-This will prints information about path. Format is a string which accepts file size in blocks (%b), filename (%n), block size (%o), replication (%r), and modification date (%y, %Y).

(22)-tail [-f] < file2name>:-This shows the last 1KB of file on stdout.

(23)-chmod [-R] mode,mode,... < path>...:-This will Change the file permissions associated with one or more objects identified by path.Performs changes recursively with R. mode is a 3-digit octal mode

(24)-chown [-R] [owner][:[group]] < path>...:-Sets the owning user and/or group for files or directories identified by path.... Sets owner recursively if -R is specified.

(25)-chgrp [-R] group < path>...:-Sets the owning group for files or directories identified by path.... Sets group recursively if -R is specified.

(26)-help < cmd-name>:-This will returns usage information for one of the commands listed above. we must omit the leading '-' character in cmd.

Other Important Questions
What is Big Data
List all daemons required to run Hadoop cluster
Typical block size of HDFS block
In which language Hadoop is written and Harware best for Hadoop
What are the most common input formats in Hadoop

Hello Sir/Madam as Covid is spreading we request you to please take care your self and visit helpsthepoor.com

Top Searches:asp net questions vb net questions sql query uddl questions class javascript sharepoint interview questions and concept silverlight questions and concept wcf questions beans general knowledge ajax questions
PHP | Biztalk | Testing | SAP | HR |