hadoop mfs commands

                    Useful hadoop mfs Command

1.     Display the usage statement for the hadoop mfs command

$ hadoop mfs

2.     Command to create symlinks in hadoop cluster

$ hadoop mfs -ln <target> <symlink>

3.     Determine which servers are storing chunks for those files

$ hadoop mfs –ls ~/mydir

4.     Determine if your subdirectory has compression turned on

$ hadoop mfs –lsd ~/mydir

5.     Lists files in the directory specified by <path>, with an additional column that displays the number of disk blocks per file. Disk blocks are 8192 bytes (8k)

$  hadoop mfs -lss /user

6.     Set the chunk size to 64K for your subdirectory

$ hadoop mfs -setchunksize 65536 ~/mydir

7.     Lists all paths recursively without crossing volume links

$ hadoop mfs -lsrv /user

8.     Lists the file name for the FID which is feeded to the command.

$ hadoop mfs -lsfid <cid.cinum.uniq>

9.     Turn off compression

$ hadoop mfs -setcompression off ~/mydir