[MAPREDUCE-643] distcp -pugp error message is not clear when chgrp fail.

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Incomplete
• Component/s: distcp
• Assignee: Unassigned
• Reporter: Aaron Kimball
• Created: 11/Jun/09 23:47
• Updated: 22/Jul/14 21:11
• Resolved: 22/Jul/14 21:11

Description

To achieve rsync-like behavior between a local directory and an HDFS instance, a pseudo-distributed MapReduce cluster was started, connected to a fully distributed HDFS instance. An initial distcp from HDFS down to the local fileystem succeeded. The following day, another distcp was run with:

$ bin/hadoop distcp -pugp -update hdfs://nn:7276/data/raw file:///data/raw

It failed; its output is below:

09/06/07 13:14:51 INFO tools.DistCp: srcPaths=[hdfs://nn:7276/data/raw]
09/06/07 13:14:51 INFO tools.DistCp: destPath=file:/data/raw
09/06/07 13:14:55 INFO tools.DistCp: srcCount=10955
09/06/07 13:14:56 INFO mapred.JobClient: Running job: job_200906071310_0001
09/06/07 13:14:57 INFO mapred.JobClient: map 0% reduce 0%
09/06/07 13:15:24 INFO mapred.JobClient: map 1% reduce 0%
09/06/07 13:17:34 INFO mapred.JobClient: map 2% reduce 0%
09/06/07 13:20:04 INFO mapred.JobClient: map 3% reduce 0%
09/06/07 13:20:49 INFO mapred.JobClient: map 4% reduce 0%
09/06/07 13:21:44 INFO mapred.JobClient: map 5% reduce 0%
09/06/07 13:22:33 INFO mapred.JobClient: map 6% reduce 0%
09/06/07 13:25:14 INFO mapred.JobClient: map 7% reduce 0%
09/06/07 13:27:14 INFO mapred.JobClient: map 8% reduce 0%
09/06/07 13:33:34 INFO mapred.JobClient: map 9% reduce 0%
09/06/07 13:37:30 INFO mapred.JobClient: map 10% reduce 0%
09/06/07 13:40:05 INFO mapred.JobClient: map 11% reduce 0%
09/06/07 13:44:55 INFO mapred.JobClient: map 12% reduce 0%
09/06/07 13:48:55 INFO mapred.JobClient: map 13% reduce 0%
09/06/07 13:54:41 INFO mapred.JobClient: map 14% reduce 0%
09/06/07 13:58:30 INFO mapred.JobClient: map 15% reduce 0%
09/06/07 14:00:46 INFO mapred.JobClient: map 16% reduce 0%
09/06/07 14:01:36 INFO mapred.JobClient: map 17% reduce 0%
09/06/07 14:04:12 INFO mapred.JobClient: map 13% reduce 0%
09/06/07 14:04:12 INFO mapred.JobClient: Task Id : attempt_200906071310_0001_m_000006_0, Status : FAILED
java.io.IOException: Copied: 0 Skipped: 264 Failed: 39
at org.apache.hadoop.tools.DistCp$CopyFilesMapper.close(DistCp.java:542) at org.apache.hadoop.mapred.MapRunner.run(MapRunner.java:50)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:227)
at org.apache.hadoop.mapred.TaskTracker$Child.main(TaskTracker.java:2210)

09/06/07 14:04:19 INFO mapred.JobClient: Task Id : attempt_200906071310_0001_m_000006_1, Status : FAILED
java.io.FileNotFoundException: File does not exist: hdfs://nn:7276/tmp/hadoop/mapred/system/distcp_m8n2e/_distcp_src_files
at org.apache.hadoop.dfs.DistributedFileSystem.getFileStatus(DistributedFileSystem.java:412)
at org.apache.hadoop.fs.FileSystem.getLength(FileSystem.java:684)
at org.apache.hadoop.io.SequenceFile$Reader.<init>(SequenceFile.java:1420)
at org.apache.hadoop.io.SequenceFile$Reader.<init>(SequenceFile.java:1415)
at org.apache.hadoop.mapred.SequenceFileRecordReader.<init>(SequenceFileRecordReader.java:43)
at org.apache.hadoop.tools.DistCp$CopyInputFormat.getRecordReader(DistCp.java:272)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:219)
at org.apache.hadoop.mapred.TaskTracker$Child.main(TaskTracker.java:2210)

(several more tasks fail for the same reason with FileNotFoundException)

With failures, global counters are inaccurate; consider running with -i
Copy failed: java.io.IOException: Job failed!
at org.apache.hadoop.mapred.JobClient.runJob(JobClient.java:1113)
at org.apache.hadoop.tools.DistCp.copy(DistCp.java:619)
at org.apache.hadoop.tools.DistCp.run(DistCp.java:768)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:65)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:79)
at org.apache.hadoop.tools.DistCp.main(DistCp.java:788)

This distcp update operation does succeed without -pugp.