問題描述： org.apache.hadoop.ipc.RemoteException(java.io.IOException): File /tmp/hadoop-yarn/staging/hadoop/.staging/job_1519998981934_0001/job.jar could only be replicated to 0 nodes instead of minReplication (=1). There are 0 datanode(s) running and no node(s) are excluded in this operation.
問題分析：There are 0 datanode(s) 使用jps查看有哪些進程正在運行，發現datanode節點沒有在運行說明是由於該節點沒有正常啟動導致數據無法存放，從而發生錯誤。
問題解決：停止現在運行的所有進程，然后重新啟動。主要是 datanode.