You are viewing a plain text version of this content. The canonical link for it is here.
Posted to hdfs-dev@hadoop.apache.org by "Yongjun Zhang (JIRA)" <ji...@apache.org> on 2014/03/25 00:44:42 UTC

[jira] [Created] (HDFS-6152) distcp V2 doesn't preserve root dir's attributes when -p is specified

Yongjun Zhang created HDFS-6152:
-----------------------------------

             Summary: distcp V2 doesn't preserve root dir's attributes when -p is specified
                 Key: HDFS-6152
                 URL: https://issues.apache.org/jira/browse/HDFS-6152
             Project: Hadoop HDFS
          Issue Type: Bug
          Components: hdfs-client
    Affects Versions: 2.3.0
            Reporter: Yongjun Zhang


Two issues were observed with distcpV2

ISSUE 1. when copying a source dir to target dir with "-pu" option using command 

  "distcp -pu source-dir target-dir"
 
The source dir's owner is not preserved at target dir. Simiarly other attributes of source dir are not preserved.  Supposedly they should be preserved when no -update and no -overwrite specified. 

There are two scenarios with the above command:

a. when target-dir already exists. Issuing the above command will  result in target-dir/source-dir (source-dir here refers to the last component of the source-dir path in the command line) at target file system, with all contents in source-dir copied to under target-dir/src-dir. The issue in this case is, the attributes of src-dir is not preserved.

b. when target-dir doesn't exist. It will result in target-dir with all contents of source-dir copied to under target-dir. This issue in this  case is, the attributes of source-dir is not carried over to target-dir.

For multiple source cases, e.g., command 

  "distcp -pu source-dir1 source-dir2 target-dir"

No matter whether the target-dir exists or not, the multiple sources are copied to under the target dir (target-dir is created if it didn't exist). And their attributes are preserved. 

ISSUE 2. with the following command:

distcp source-dir target-dir

when source-dir is an empty directory, and when target-dir doesn't exist, source-dir is not copied, actually the command behaves like a no-op. 

However, when the source-dir is not empty, it would be copied and results in target-dir at the target file system containing a copy of source-dir's children.

To be consistent, empty source dir should be copied too. Basically the  above distcp command should cause target-dir get created at target file 
system, and the source-dir's attributes are preserved at target-dir when 
-p is passed.




--
This message was sent by Atlassian JIRA
(v6.2#6252)