yarn重启后，部分nm启动不了，报空指针问题
2015-03-26 07:41:00,367 INFO org.apache.hadoop.yarn.server.nodemanager.containermanager.localizer.LocalizedResource: Resource hdfs://:8020/user/hive/.staging/job_1426073522130_3022/libjars/guava-11.0.2.jar(->/data7/yarn/nm/usercache/hive/filecache/84380/guava-11.0.2.jar) transitioned from INIT to LOCALIZED
2015-03-26 07:41:00,391 INFO org.apache.hadoop.service.AbstractService: Service org.apache.hadoop.yarn.server.nodemanager.containermanager.ContainerManagerImpl failed in state INITED; cause: java.lang.NullPointerException
java.lang.NullPointerException
at org.apache.hadoop.yarn.server.nodemanager.containermanager.ContainerManagerImpl.recoverContainer(ContainerManagerImpl.java:289)
at org.apache.hadoop.yarn.server.nodemanager.containermanager.ContainerManagerImpl.recover(ContainerManagerImpl.java:252)
at org.apache.hadoop.yarn.server.nodemanager.containermanager.ContainerManagerImpl.serviceInit(ContainerManagerImpl.java:235)
at org.apache.hadoop.service.AbstractService.init(AbstractService.java:163)
at org.apache.hadoop.service.CompositeService.serviceInit(CompositeService.java:107)
at org.apache.hadoop.yarn.server.nodemanager.NodeManager.serviceInit(NodeManager.java:250)
at org.apache.hadoop.service.AbstractService.init(AbstractService.java:163)
at org.apache.hadoop.yarn.server.nodemanager.NodeManager.initAndStartNodeManager(NodeManager.java:445)
at org.apache.hadoop.yarn.server.nodemanager.NodeManager.main(NodeManager.java:492)
2015-03-26 07:41:00,401 INFO org.apache.hadoop.yarn.server.nodemanager.containermanager.logaggregation.LogAggregationService: org.apache.hadoop.yarn.server.nodemanager.containermanager.logaggregation.LogAggregationService waiting for pending aggregation during exit
2015-03-26 07:41:00,402 INFO org.apache.hadoop.service.AbstractService: Service NodeManager failed in state INITED; cause: java.lang.NullPointerException
java.lang.NullPointerException
at org.apache.hadoop.yarn.server.nodemanager.containermanager.ContainerManagerImpl.recoverContainer(ContainerManagerImpl.java:289)
at org.apache.hadoop.yarn.server.nodemanager.containermanager.ContainerManagerImpl.recover(ContainerManagerImpl.java:252)
at org.apache.hadoop.yarn.server.nodemanager.containermanager.ContainerManagerImpl.serviceInit(ContainerManagerImpl.java:235)
at org.apache.hadoop.service.AbstractService.init(AbstractService.java:163)
at org.apache.hadoop.service.CompositeService.serviceInit(CompositeService.java:107)
at org.apache.hadoop.yarn.server.nodemanager.NodeManager.serviceInit(NodeManager.java:250)
at org.apache.hadoop.service.AbstractService.init(AbstractService.java:163)
at org.apache.hadoop.yarn.server.nodemanager.NodeManager.initAndStartNodeManager(NodeManager.java:445)
at org.apache.hadoop.yarn.server.nodemanager.NodeManager.main(NodeManager.java:492)
2015-03-26 07:41:00,403 INFO org.apache.hadoop.metrics2.impl.MetricsSystemImpl: Stopping NodeManager metrics system...
2015-03-26 07:41:00,403 INFO org.apache.hadoop.metrics2.impl.MetricsSystemImpl: NodeManager metrics system stopped.
2015-03-26 07:41:00,403 INFO org.apache.hadoop.metrics2.impl.MetricsSystemImpl: NodeManager metrics system shutdown complete.
2015-03-26 07:41:00,403 FATAL org.apache.hadoop.yarn.server.nodemanager.NodeManager: Error starting NodeManager
java.lang.NullPointerException
at org.apache.hadoop.yarn.server.nodemanager.containermanager.ContainerManagerImpl.recoverContainer(ContainerManagerImpl.java:289)
at org.apache.hadoop.yarn.server.nodemanager.containermanager.ContainerManagerImpl.recover(ContainerManagerImpl.java:252)
at org.apache.hadoop.yarn.server.nodemanager.containermanager.ContainerManagerImpl.serviceInit(ContainerManagerImpl.java:235)
at org.apache.hadoop.service.AbstractService.init(AbstractService.java:163)
at org.apache.hadoop.service.CompositeService.serviceInit(CompositeService.java:107)
at org.apache.hadoop.yarn.server.nodemanager.NodeManager.serviceInit(NodeManager.java:250)
at org.apache.hadoop.service.AbstractService.init(AbstractService.java:163)
at org.apache.hadoop.yarn.server.nodemanager.NodeManager.initAndStartNodeManager(NodeManager.java:445)
解决办法：
sudo rm -rf /tmp/hadoop-yarn/yarn-nm-recovery
参见：
http://stackoverflow.com/questions/27065011/cdh-5-2-error-starting-nodemanager-service-nodemanager-failed-in-state-inited-c