hadoop集群的NodeManager存在， 但在yarn上显示Unhealthy Nodes

也可以使用命令查看节点状态：

[mmtrix@www hadoop-2.6.0-cdh5.4.1]$ bin/yarn node -list -all

查看yarn的log发现

2020-06-08 10:31:12,900 WARN org.apache.hadoop.yarn.server.nodemanager.DirectoryCollection: Directory /home/mmtrix/application/gosun/enterprise/hadoop/hadoop-2.6.0-cdh5.4.1/logs/yarn/log error, used space above threshold of 90.0%, removing from list of valid directories
2020-06-08 10:31:12,900 INFO org.apache.hadoop.yarn.server.nodemanager.LocalDirsHandlerService: Disk(s) failed: 1/1 log-dirs are bad: /home/mmtrix/application/gosun/enterprise/hadoop/hadoop-2.6.0-cdh5.4.1/logs/yarn/log
2020-06-08 10:31:12,900 ERROR org.apache.hadoop.yarn.server.nodemanager.LocalDirsHandlerService: Most of the disks failed. 1/1 log-dirs are bad: /home/mmtrix/application/gosun/enterprise/hadoop/hadoop-2.6.0-cdh5.4.1/logs/yarn/log
2020-06-08 10:31:12,903 INFO org.apache.hadoop.yarn.event.AsyncDispatcher: Registering class org.apache.hadoop.yarn.server.nodemanager.containermanager.loghandler.event.LogHandlerEventType for class org.apache.hadoop.yarn.server.nodemanager.containermanager.logaggregation.LogAggregationService

Directory /home/mmtrix/application/gosun/enterprise/hadoop/hadoop-2.6.0-cdh5.4.1/logs/yarn/log error, used space above threshold of 90.0%, removing from list of valid directories

是node节点磁盘不够了导致的。

解决方案：

删除一些无效的磁盘文件就可以了。