Hadoop集群上跑mapreduce，在job任务执行完成退出时报 java.io.IOException: Job status not available异常。Job client请求job状态时，Application已经完成转而去Job history server请求job状态，就在这里抛出异常。

[xubc@master conf]$ hadoop jar /usr/lib/hadoop-mapreduce/hadoop-mapreduce-examples.jar wordcount /user/lizeyi/people.txt  /user/lizeyi/wordcount7
15/06/08 18:36:16 INFO client.RMProxy: Connecting to ResourceManager at master.hadoop/10.3.4.35:8032
15/06/08 18:36:17 INFO input.FileInputFormat: Total input paths to process : 1
15/06/08 18:36:17 INFO lzo.GPLNativeCodeLoader: Loaded native gpl library
15/06/08 18:36:17 INFO lzo.LzoCodec: Successfully loaded & initialized native-lzo library [hadoop-lzo rev 39cf0c71a251a79c50555810ca660450d9682140]
15/06/08 18:36:17 INFO mapreduce.JobSubmitter: number of splits:1
15/06/08 18:36:18 INFO mapreduce.JobSubmitter: Submitting tokens for job: job_1433756996622_0004
15/06/08 18:36:18 INFO impl.YarnClientImpl: Submitted application application_1433756996622_0004
15/06/08 18:36:18 INFO mapreduce.Job: The url to track the job: http://master.hadoop:8088/proxy/application_1433756996622_0004/
15/06/08 18:36:18 INFO mapreduce.Job: Running job: job_1433756996622_0004
15/06/08 18:36:40 INFO mapred.ClientServiceDelegate: Application state is completed. FinalApplicationStatus=SUCCEEDED. Redirecting to job history server
java.io.IOException: Job status not available at org.apache.hadoop.mapreduce.Job.updateStatus(Job.java:322)at org.apache.hadoop.mapreduce.Job.isComplete(Job.java:609)at org.apache.hadoop.mapreduce.Job.monitorAndPrintJob(Job.java:1354)at org.apache.hadoop.mapreduce.Job.waitForCompletion(Job.java:1316)at org.apache.hadoop.examples.WordCount.main(WordCount.java:87)at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)at java.lang.reflect.Method.invoke(Method.java:606)at org.apache.hadoop.util.ProgramDriver$ProgramDescription.invoke(ProgramDriver.java:72)at org.apache.hadoop.util.ProgramDriver.run(ProgramDriver.java:145)at org.apache.hadoop.examples.ExampleDriver.main(ExampleDriver.java:74)at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)at java.lang.reflect.Method.invoke(Method.java:606)at org.apache.hadoop.util.RunJar.main(RunJar.java:212)

须配置Job History Server相关参数，让Job Client可以读取job最后的执行状态，测试Hadoop版本2.5.0

添加参数vim mapred-site.xml

   <property><name>mapreduce.jobhistory.address</name><value>master.hadoop:10020</value></property><property><name>yarn.app.mapreduce.am.staging-dir</name><value>/tmp/hadoop-yarn/staging</value></property><property><name>mapreduce.jobhistory.intermediate-done-dir</name><value>${yarn.app.mapreduce.am.staging-dir}/history/done_intermediate</value></property><property><name>mapreduce.jobhistory.done-dir</name><value>${yarn.app.mapreduce.am.staging-dir}/history/done</value></property>

修改完成配置后，重新执行任务后正常退出

[xubc@master conf]$ hadoop jar /usr/lib/hadoop-mapreduce/hadoop-mapreduce-examples.jar wordcount /user/lizeyi/people.txt  /user/lizeyi/wordcount9
15/06/08 18:54:04 INFO client.RMProxy: Connecting to ResourceManager at master.hadoop/10.3.4.35:8032
15/06/08 18:54:06 INFO input.FileInputFormat: Total input paths to process : 1
15/06/08 18:54:06 INFO lzo.GPLNativeCodeLoader: Loaded native gpl library
15/06/08 18:54:06 INFO lzo.LzoCodec: Successfully loaded & initialized native-lzo library [hadoop-lzo rev 39cf0c71a251a79c50555810ca660450d9682140]
15/06/08 18:54:06 INFO mapreduce.JobSubmitter: number of splits:1
15/06/08 18:54:06 INFO mapreduce.JobSubmitter: Submitting tokens for job: job_1433760669916_0001
15/06/08 18:54:07 INFO impl.YarnClientImpl: Submitted application application_1433760669916_0001
15/06/08 18:54:07 INFO mapreduce.Job: The url to track the job: http://master.hadoop:8088/proxy/application_1433760669916_0001/
15/06/08 18:54:07 INFO mapreduce.Job: Running job: job_1433760669916_0001
15/06/08 18:54:34 INFO mapred.ClientServiceDelegate: Application state is completed. FinalApplicationStatus=SUCCEEDED. Redirecting to job history server
15/06/08 18:54:35 INFO mapreduce.Job: Job job_1433760669916_0001 running in uber mode : false
15/06/08 18:54:35 INFO mapreduce.Job:  map 100% reduce 100%
15/06/08 18:54:35 INFO mapreduce.Job: Job job_1433760669916_0001 completed successfully
15/06/08 18:54:35 INFO mapreduce.Job: Counters: 49File System CountersFILE: Number of bytes read=68FILE: Number of bytes written=205241FILE: Number of read operations=0FILE: Number of large read operations=0FILE: Number of write operations=0HDFS: Number of bytes read=151HDFS: Number of bytes written=46HDFS: Number of read operations=6HDFS: Number of large read operations=0HDFS: Number of write operations=2Job Counters Launched map tasks=1Launched reduce tasks=1Data-local map tasks=1Total time spent by all maps in occupied slots (ms)=6036Total time spent by all reduces in occupied slots (ms)=6132Total time spent by all map tasks (ms)=6036Total time spent by all reduce tasks (ms)=6132Total vcore-seconds taken by all map tasks=6036Total vcore-seconds taken by all reduce tasks=6132Total megabyte-seconds taken by all map tasks=6180864Total megabyte-seconds taken by all reduce tasks=6279168Map-Reduce FrameworkMap input records=4Map output records=4Map output bytes=54Map output materialized bytes=68Input split bytes=113Combine input records=4Combine output records=4Reduce input groups=4Reduce shuffle bytes=68Reduce input records=4Reduce output records=4Spilled Records=8Shuffled Maps =1Failed Shuffles=0Merged Map outputs=1GC time elapsed (ms)=82CPU time spent (ms)=2150Physical memory (bytes) snapshot=447897600Virtual memory (bytes) snapshot=1986359296Total committed heap usage (bytes)=355467264Shuffle ErrorsBAD_ID=0CONNECTION=0IO_ERROR=0WRONG_LENGTH=0WRONG_MAP=0WRONG_REDUCE=0File Input Format Counters Bytes Read=38File Output Format Counters Bytes Written=46

参考文章：https://support.pivotal.io/hc/en-us/articles/201180246-IOException-Job-status-not-available-when-mapreduce-job-exits-successfully

http://stackoverflow.com/questions/23182642/yarn-in-aazon-ec2-with-whirr