Hadoop/HDFS: put 命令失败 - 没有这样的文件或目录

Question

I do not know why I cannot move a file from one directory to another. I can view the content of the file but I cannot move the same file into another directory.

WORKS FINE:

hadoop fs -cat /user/hadoopusr/project-data.txt

DOES NOT WORK:

hadoop fs -put /user/hadoopusr/project-data.txt /user/hadoopusr/Projects/MarketAnalysis

I got a No such file or directory error message. What is wrong? Please help. Thank you!

Answer 1

As we can read from here about the -put command:

This command is used to copy files from the local file system to the HDFS filesystem . This command is similar to –copyFromLocal command. This command will not work if the file already exists unless the –f flag is given to the command. This overwrites the destination if the file already exists before the copy

Which makes it clear why it doesn't work and throws the No such file or directory message. It's because it can't find any file with the name project-data.txt on your current directory of your local filesystem.

You plan on moving a file between directories inside the HDFS, so instead of using the -put parameter for moving, we can simply use the -mv parameter as we would in our local filesystem!

Tested it out on my own HDFS as follows:

1. Create the source and destination directories in HDFS

hadoop fs -mkdir source_dir dest_dir

2. Create an empty (for the sake of the test) file under the source directory

hadoop fs -touch source_dir/test.txt

3. Move the empty file to the destination directory

hadoop fs -mv source_dir/test.txt dest_dir/test.txt

(Notice how the /user/username/ part of the path for the file and the destination directory is not needed, because HDFS is by default on this directory where you are working. You also should note that you have to write the full path of the destination with name of the file included .)

You can see below with the HDFS browser that the empty text file has been moved to the destination directory: