hadoop-3.0.0 配置中的 yarn.nodemanager.aux-services 项

在hadoop-3.0.0-alpha4 的配置中，yarn.nodemanager.aux-services项的默认值是“mapreduce.shuffle”，但如果在hadoop-2.2 中继续使用这个值，NodeManager 会启动失败，在logs/yarn-biadmin-nodemanager-hostname.log里会报如下的错：

java.lang.IllegalArgumentException: The ServiceName: mapreduce.shuffle set in yarn.nodemanager.aux-services is invalid.The valid service name should only contain a-zA-Z0-9_ and can not start with numbers

at com.google.common.base.Preconditions.checkArgument(Preconditions.java:88)

at org.apache.hadoop.yarn.server.nodemanager.containermanager.AuxServices.serviceInit(AuxServices.java:115)

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.containermanager.ContainerManagerImpl.serviceInit(ContainerManagerImpl.java:303)

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:406)

at org.apache.hadoop.service.AbstractService.init(AbstractService.java:163)

at org.apache.hadoop.yarn.server.nodemanager.NodeManager.initAndStartNodeManager(NodeManager.java:748)

at org.apache.hadoop.yarn.server.nodemanager.NodeManager.main(NodeManager.java:809)

2017-07-21 03:21:42,946 INFO org.apache.hadoop.yarn.server.nodemanager.NodeManager: SHUTDOWN_MSG: 

/************************************************************

SHUTDOWN_MSG: Shutting down NodeManager at slave1/127.0.0.1

************************************************************/

解决方案：

将yarn.nodemanager.aux-services项的值"mapreduce.shuffle"改为“mapreduce_shuffle”。

注意：需要在每个节点的yarn-site.xml上改，位置：/usr/hadoop/hadoop-3.0.0-alpha4/etc/hadoop