Hi,
Any ideas why a staging directory would suddenly become unavailable
after the completion of the map phase but before the start of the
reduce phase? We noticed a sporadic failure yesterday wherein all the
map tasks completed
successfully and all the reduce tasks failed. Upon examining task
tracker logs, the following exception stack trace was revealed:
2013-01-03 02:28:17,072 WARN org.apache.hadoop.mapred.TaskTracker:
Error initializing attempt_201211150255_237458_r_000108_1:
java.io.FileNotFoundException: File does not exist:
hdfs://59.bm-hadoop.prod.nym2:54310/user/apache/.staging/job_201211150255_237458/job.xml
at
org.apache.hadoop.hdfs.DistributedFileSystem.getFileStatus(DistributedFileSystem.java:562)
at org.apache.hadoop.fs.FileUtil.copy(FileUtil.java:207)
at org.apache.hadoop.fs.FileUtil.copy(FileUtil.java:157)
at org.apache.hadoop.fs.FileSystem.copyToLocalFile(FileSystem.java:1371)
at org.apache.hadoop.fs.FileSystem.copyToLocalFile(FileSystem.java:1352)
at
org.apache.hadoop.mapred.TaskTracker.localizeJobConfFile(TaskTracker.java:1434)
at
org.apache.hadoop.mapred.TaskTracker.initializeJob(TaskTracker.java:1318)
at
org.apache.hadoop.mapred.TaskTracker.localizeJob(TaskTracker.java:1242)
at
org.apache.hadoop.mapred.TaskTracker.startNewTask(TaskTracker.java:2541)
at
org.apache.hadoop.mapred.TaskTracker$TaskLauncher.run(TaskTracker.java:2505)
This problem doesn't seem relevant to only a specific distribution,
but for completeness we are running CDH3u3.
Thanks!
stan