The commands on HDFS are generally quite similar to the commands on Linux, both in terms of their functions and names, if you are familiar with Linux/Ubuntu then you probably don’t need to learn much, so apply. just use it.
help
Ask about common line in HDFS :
1
2
hdfs dfs -help
hdfs dfs -usege <utility_name>
Ask about a specific command:
1
2
hdfs dfs -help <statement>
VD: hdfs dfs -help ls
mkdir
Make folder in HDFS:
1
hdfs dfs -mkdir /newfolder
Make folder if this already exists, add parameter:
1
hdfs dfs -mkdir -p /newfolder
ls
Display folder and file in directory:
1
hdfs dfs -ls /
Display folder and file in directory and all subfolder in this:
1
hdfs dfs -ls -R /
put
Copy file from local folder to HDFS folder:
1
2
hdfs dfs -put ~/test.txt /newfolder/
hdfs dfs -copyFromLocal ~/test.txt /newfolder/
get
Copy file from HDFS folder to local folder:
1
2
hdfs dfs -get /newfolder/test.txt /copyfromhdfs/
hdfs dfs -copyToLocal /newfolder/test.txt /copyfromhdfs/
cat
Check content in file:
1
hdfs dfs -cat /newfolder/test.txt
mv
Move file or folder from folder to folder:
1
hdfs dfs -mv /newfolder /DR
cp
Copy file or folder from folder to folder:
1
hdfs dfs -cp /DR/newfolder/test.txt /DR
rm
Delete file in HDFS:
1
hdfs dfs -rm /DR/test.txt
getmerge
Merge file in HDFS and download to local:
1
hdfs dfs -getmerge /usr/trannguyenhan /home/trannguyenhan01092000/output.dat