问题
I am trying to add capacity scheduler in hadoop 0.23.0 and trying to run a sample pi, randomwriter program.
All the daemons are up and working fine, but the job is getting hanged and no more output is getting displayed.
I couldnt able to see the logs where they are accumulated. Can anyone please let me know the reason for this hanging of the job, and location where the logs are stored.
2012-06-08 18:41:06,118 INFO mapred.YARNRunner (YARNRunner.java:createApplicationSubmissionContext(355)) - Command to launch container for ApplicationMaster is : $JAVA_HOME/bin/java -Dlog4j.configuration=container-log4j.properties -Dyarn.app.mapreduce.container.log.dir=<LOG_DIR> -Dyarn.app.mapreduce.container.log.filesize=0 -Dhadoop.root.logger=INFO,CLA -Xmx1536m org.apache.hadoop.mapreduce.v2.app.MRAppMaster 1><LOG_DIR>/stdout 2><LOG_DIR>/stderr
2012-06-08 18:41:06,251 INFO mapred.ResourceMgrDelegate (ResourceMgrDelegate.java:submitApplication(304)) - Submitted application application_1339151256291_0003 to ResourceManager
2012-06-08 18:41:06,355 INFO mapreduce.Job (Job.java:monitorAndPrintJob(1207)) - Running job: job_1339151256291_0003
2012-06-08 18:41:07,366 INFO mapreduce.Job (Job.java:monitorAndPrintJob(1227)) - map 0% reduce 0%
回答1:
I followed the instructions on http://www.thecloudavenue.com/search?q=0.23 and successfully run Hadoop-0.23.4 on a small 3 node cluster.
Check the log files in the
$HADOOP_HOME/logs
folder for any errors on the master and the slaves.
Check for the following console
//master:50070/dfshealth.jsp
Check if the number of DataNodes is correct in
//master:50070/dfsnodelist.jsp?whatNodes=LIVE
Check if the number of NodeManagers is correctly reported in
//master:8088/cluster
Also the number of NodeManagers should be correctly specified in
//master:8088/cluster/nodes
Verify that the output folder with the proper contents has been created through the NameNode Web console
//master:50070/nn_browsedfscontent.jsp
来源：https://stackoverflow.com/questions/10942601/job-hanging-when-example-run-on-hadoop-0-23-0