Hadoop：从源（即我的PC）将文件加载到HDFS时出现错误

Question

Im trying to copy a file from source to hdfs

Query: Hadoop fs -copyFromLocal (Local path) (source path)

eg Hadoop fs -copyFromLocal C:\\users\\Desktop (source path)

as well eg Hadoop fs -copyFromLocal C:\\users\\Desktop URI

but geting error

-copyFromLocal: Can not create a Path from a null string Usage: hadoop fs [generic options] -copyFromLocal [-f] [-p] (localsrc) ... (dst)

Answer 1

try hadoop dfs -copyFromLocal file_to_be_copied hdfs://namenode:/path_to_location

fs command is being depreciated.

Note: you do not have to mention the actual HDFS path. You could also do something like

hadoop dfs -copyFromLocal file_to_be_copied /path_to_location_within_hdfs

Answer 2

1. You are not specifying the path of file.
2. Make sure hdfs path that you specified exists.

3. Finally try escaping the forward slash like:

    Hadoop fs -copyFromLocal C:\\\\users\\\\Desktop\\myfile.txt URI 

Or use

    Hadoop fs -copyFromLocal C:/users/Desktop/myfile.txt URI

Answer 3

Unfortunately, I am unable to comment below your reply. The easiest way to to get the path is to go under the UI and click on "Browse the filesystem". Another option would be to hdfs dfs -ls / or hdfs dfs -lsr /

ls will list the dir/files in your root dir.
lsr will recursively read through all the sub directories in your root dir.

Answer 4

HDFS is just like other file systems. The path begins with / as root. The period (.) denotes current directory. I am on Linux platform. Hope the examples below would help.

name@host: ~/oracle/sql$ hdfs dfs -ls /
Found 5 items
drwxr-xr-x   - myname supergroup          0 2014-09-05 03:06 /directory
drwxr-xr-x   - myname supergroup          0 2014-05-10 03:34 /in
drwxr-xr-x   - myname supergroup          0 2014-10-16 22:50 /system
drwxrwx---   - myname supergroup          0 2014-08-18 08:44 /tmp
drwxr-xr-x   - myname supergroup          0 2014-08-18 08:41 /user
name@host: ~/oracle/sql$ hdfs dfs -copyFromLocal foo.sql /
name@host: ~/oracle/sql$ hdfs dfs -ls /
Found 6 items
drwxr-xr-x   - myname supergroup          0 2014-09-05 03:06 /directory
-rw-r--r--   3 myname supergroup         90 2015-03-24 05:33 /foo.sql
drwxr-xr-x   - myname supergroup          0 2014-05-10 03:34 /in
drwxr-xr-x   - myname supergroup          0 2014-10-16 22:50 /system
drwxrwx---   - myname supergroup          0 2014-08-18 08:44 /tmp
drwxr-xr-x   - myname supergroup          0 2014-08-18 08:41 /user

name@name: ~/oracle/sql$ hdfs dfs -copyFromLocal foo.sql /user/myname/
name@name: ~/oracle/sql$ hdfs dfs -ls /user/myname/foo.sql
-rw-r--r--   3 myname supergroup         90 2015-03-24 05:41       /user/myname/foo.sql
name@host: ~/oracle/sql$