hadoop fs is space-sensitive
HDFS, high density file system, is useful for big data. However, hadoop fs is not quite there as a shell replacement. Today I kept getting the message
cp: When copying multiple files, destination should be a directory.
when trying to copy multiple files to a directory using
hadoop fs -cp /path/to/files/* /path/to/destination/directory
Finally figured out that the problem was I had two spaces between the file list and the directory path, which made hadoop not see the directory path in the command. Aaahh.