通过history server
通过history server，直接在web ui上查看（如果任务异常退出，可能会看不到）
通过yarn命令(用户要和提交任务的用户一致）
yarn application -list -appStates ALL（这个不显示时间信息）
代码语言：javascript复制[hdfs@node1 opt]$ yarn application -list -appStates ALL
17/07/26 10:51:33 INFO impl.TimelineClientImpl: Timeline service address: http://node2.hde.h3c.com:8188/ws/v1/timeline/
17/07/26 10:51:33 INFO client.RMProxy: Connecting to ResourceManager at node2.hde.h3c.com/192.38.0.232:8050
Total number of applications (application-types: [] and states: [NEW, NEW_SAVING, SUBMITTED, ACCEPTED, RUNNING, FINISHED, FAILED, KILLED]):2
Application-Id Application-Name Application-Type User Queue State Final-State Progress Tracking-URL
application_1500702983136_0002 word count MAPREDUCE ambari-qa default FINISHED SUCCEEDED 100% http://node2.hde.h3c.com:19888/jobhistory/job/job_1500702983136_0002
application_1500702983136_0001 DistributedShell YARN ambari-qa default FINISHED SUCCEEDED 100% N/Ayarn logs -applicationId application_1493700892407_0007
代码语言：javascript复制[ambari-qa@node1 opt]$ yarn logs -applicationId application_1500702983136_0002
17/07/26 10:56:23 INFO impl.TimelineClientImpl: Timeline service address: http://node2.hde.h3c.com:8188/ws/v1/timeline/
17/07/26 10:56:23 INFO client.RMProxy: Connecting to ResourceManager at node2.hde.h3c.com/192.38.0.232:8050
17/07/26 10:56:25 INFO zlib.ZlibFactory: Successfully loaded & initialized native-zlib library
17/07/26 10:56:25 INFO compress.CodecPool: Got brand-new decompressor [.deflate]
Container: container_1500702983136_0002_01_000002 on node1.hde.h3c.com_45454
==============================================================================
LogType:stderr
Log Upload Time:Sat Jul 22 01:59:41 -0400 2017
LogLength:0
Log Contents:
End of LogType:stderr
LogType:stdout
Log Upload Time:Sat Jul 22 01:59:41 -0400 2017
LogLength:0
Log Contents:
End of LogType:stdout
LogType:syslog
Log Upload Time:Sat Jul 22 01:59:41 -0400 2017
LogLength:3674
Log Contents:
2017-07-22 01:59:16,446 WARN [main] org.apache.hadoop.metrics2.impl.MetricsConfig: Cannot locate configuration: tried hadoop-metrics2-maptask.properties,hadoop-metrics2.properties直接查看hdfs路径的log
查看yarn-site.xml，确定log配置目录
代码语言：javascript复制<property>
<name>yarn.nodemanager.remote-app-log-dir</name>
<value>/app-logs</value>
</property>
```
2）查看日志文件信息（注意日期和时间）
[hdfs@node1 root]$ hdfs dfs -ls /app-logs/hdfs/logs
Found 1 items
drwxrwx--- - hdfs hadoop 0 2017-05-02 04:18 /app-logs/hdfs/logs/application_1493700892407_0007
3）查看日志详情（注意查看节点重启前的几个敏感app）
yarn logs -applicationId application_1493700892407_0007（同2）
