Hi Pavan, Do you see this happen on a specific node every time (i.e. when the reducer runs there)?
On Fri, Aug 10, 2012 at 11:43 PM, Pavan Kulkarni <pavan.babu...@gmail.com> wrote: > Hi, > > I am running a Terasort with a cluster of 8 nodes.The map phase completes > but when the reduce phase is around 68-70% I get this following error. > > * > 12/08/10 11:02:36 INFO mapred.JobClient: Task Id : > attempt_201208101018_0001_r_000027_0, Status : FAILED > java.lang.RuntimeException: problem advancing post rec#38320220 > * > * at > org.apache.hadoop.mapred.Task$ValuesIterator.next(Task.java:1214)* > * at > org.apache.hadoop.mapred.ReduceTask$ReduceValuesIterator.moveToNext(ReduceTask.java:249) > * > * at > org.apache.hadoop.mapred.ReduceTask$ReduceValuesIterator.next(ReduceTask.java:245) > * > * at > org.apache.hadoop.mapred.lib.IdentityReducer.reduce(IdentityReducer.java:40) > * > * at > org.apache.hadoop.mapred.ReduceTask.runOldReducer(ReduceTask.java:519)* > * at org.apache.hadoop.mapred.ReduceTask.run(ReduceTask.java:420)* > * at org.apache.hadoop.mapred.Child$4.run(Child.java:255)* > * at java.security.AccessController.doPrivileged(Native Method)* > * at javax.security.auth.Subject.doAs(Subject.java:416)* > * at > org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1093) > * > * at org.apache.hadoop.mapred.Child.main(Child.java:249)* > *Caused by: org.apache.hadoop.fs.ChecksumException: Checksum Error* > * at > org.apache.hadoop.mapred.IFileInputStream.doRead(IFileInputStream.java:164)* > * at > org.apache.hadoop.mapred.IFileInputStream.read(IFileInputStream.java:101)* > * at org.apache.hadoop.mapred.IFile$Reader.readData(IFile.java:328)* > * at org.apache.hadoop.mapred.IFile$Reader.rejigData(IFile.java:358)* > * at > org.apache.hadoop.mapred.IFile$Reader.readNextBlock(IFile.java:342)* > * at org.apache.hadoop.mapred.IFile$Reader.next(IFile.java:374)* > * at org.apache.hadoop.mapred.Merger$Segment.next(Merger.java:220)* > * at > org.apache.hadoop.mapred.Merger$MergeQueue.adjustPriorityQueue(Merger.java:330) > * > * at org.apache.hadoop.mapred.Merger$MergeQueue.next(Merger.java:350) > * > * at > org.apache.hadoop.mapred.ReduceTask$ReduceCopier$RawKVIteratorReader.next(ReduceTask.java:2531) > * > * at org.apache.hadoop.mapred.Merger$Segment.next(Merger.java:220)* > * at > org.apache.hadoop.mapred.Merger$MergeQueue.adjustPriorityQueue(Merger.java:330) > * > * at org.apache.hadoop.mapred.Merger$MergeQueue.next(Merger.java:350) > * > * at > org.apache.hadoop.mapred.Task$ValuesIterator.readNextKey(Task.java:1253)* > * at > org.apache.hadoop.mapred.Task$ValuesIterator.next(Task.java:1212)* > * ... 10 more* > > I came across somone facing the same > issue<http://mail-archives.apache.org/mod_mbox/hadoop-common-user/201001.mbox/%3c1c802db51001280427j5b8e57dai4a8d0fdd038...@mail.gmail.com%3E>in > the mail-archives and he seemed to resolve it by listing hostnames in > the */etc/hosts *file, > but all my nodes have correct info about the hostnames in /etc/hosts, but I > still have these reducers throwing error. > Any help regarding this issue is appreciated .Thanks > > -- > > --With Regards > Pavan Kulkarni -- Harsh J
