2020-03-14 22:49:47,051 INFO [org.apache.hadoop.ipc.Client] - Retrying connect to server: hadoop100/192.168.10.100:9000. Already tried 0 time(s); maxRetries=45
可能是防火牆沒有關閉
Exception in thread "main" org.apache.hadoop.ipc.RemoteException(org.apache.hadoop.hdfs.server.namenode.SafeModeException): Cannot create file/nz1908-3.dat. Name node is in safe mode.
Resources are low on NN. Please add or free up more resources then turn off safe mode manually. NOTE: If you turn off safe mode before adding resources, the NN will immediately return to safe mode. Use "hdfs dfsadmin -safemode leave" to turn safe mode off.
強制退出安全模式
hdfs dfsadmin -safemode leave
Exception in thread "main" org.apache.hadoop.ipc.RemoteException(java.io.IOException): File /nz1908-3.dat could only be replicated to 0 nodes instead of minReplication (=1). There are 1 datanode(s) running and no node(s) are excluded in this operation.