Hi Guru, Still same error. This problem is with host name resolution according to log.
Vaibhav Negi On Tue, Sep 28, 2010 at 8:16 PM, Guru Prasad <guru.pra...@ibibogroup.com>wrote: > > Try running > "select count(1) from table;" > > Thanks & Regards > ~guru > > On 09/28/2010 08:07 PM, vaibhav negi wrote: > >> Hi, >> >> I am using hadoop version 0.20.2 >> >> While running query "select count(*) from table;" on Hive,i am getting >> this error >> >> FAILED: Execution Error, return code 2 from >> org.apache.hadoop.hive.ql.exec.MapRedTask >> >> Error in task tracker logs says :- >> >> Error: java.lang.NullPointerException >> at java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:768) >> at >> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.getMapCompletionEvents(ReduceTask.java:2683) >> at >> org.apache.hadoop.mapred.ReduceTask$ReduceCopier$GetMapEventsThread.run(ReduceTask.java:2605) >> >> On debugging i found that ReduceTask.java:2683 line is using host which >> is coming null >> >> ReduceTask.java:2683 --- >> List loc = mapLocations.get(host); >> >> One user in Hadoop Forum says HADOOP-4744 should be included in hadoop. Is >> this patch required for hadoop 0.20.2 ? >> How to add patch? >> >> Is this an issue with /etc/hosts file? >> >> Please help >> >> Regards >> Vaibhav Negi >> > > This message is intended only for the use of the addressee and may contain > information that is privileged, confidential and exempt from disclosure > under applicable law. If the reader of this message is not the intended > recipient, or the employee or agent responsible for delivering the message > to the intended recipient, you are hereby notified that any dissemination, > distribution or copying of this communication is strictly prohibited. If you > have received this e-mail in error, please notify us immediately by return > e-mail and delete this e-mail and all attachments from your system. > >
