1> Check access to HDFS (Operations on Namenode)
#./hadoop-0.20.2/bin/hadoop Fs-ls
File system operations in 2> Hadoop
#./hadoop-0.20.2/bin/hadoop Fs-mkdir Test
#./hadoop-0.20.2/bin/hadoop Fs-ls Test
#./hadoop-0.20.2/bin/hadoop FS-RMR Test
3> Test Hadoop
A> Create a subdirectory
#./hadoop-0.20.2/bin/hadoop Fs-mkdir Input
B> move local files to HDFs
#./hadoop-0.20.2/bin/hadoop Fs-put/usr/share/doc/pam-1.1.1/rfc86.0.txt Input
#./hadoop-0.20.2/bin/hadoop Fs-put/usr/share/doc/pam-1.1.1/linux-pam_sag.txt Input
c> See if a file exists
#./hadoop-0.20.2/bin/hadoop Fs-ls Input
D> perform mapreduce jobs that calculate the frequency of words
#./hadoop-0.20.2/bin/hadoop Jar/root/hadoop-0.20.2/hadoop-0.20.2-examples.jar wordcount Input Output
Found 2 Items
Drwxr-xr-x-root supergroup 0 2012-11-26 04:25/user/root/output/_logs
-rw-r--r--2 root supergroup 8315 2012-11-26 04:25/user/root/output/part-r-00000
e> View Output Results
#./hadoop-0.20.2/bin/hadoop Fs-ls Output
#./hadoop-0.20.2/bin/hadoop Fs-cat output/part-r-00000 | Head-n 13
F> extract output from HDFs
#./hadoop-0.20.2/bin/hadoop Fs-get output/part-r-00000 output.txt