搭建好Hadoop集群之后使用hdfs命令上传文件到hdfs报错：
hdfs dfs -put jn_gaj_lgxx.csv /input
报错内容如下所示：
[root@master local]# hdfs dfs -put jn_gaj_lgxx.csv /input
19/08/21 15:55:40 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applic able
19/08/21 15:55:42 WARN hdfs.DataStreamer: DataStreamer Exception
org.apache.hadoop.ipc.RemoteException(java.io.IOException): File /input/jn_gaj_lgxx.csv._COPYING_ could only be replicated to 0 nodes instead o f minReplication (=1). There are 0 datanode(s) running and no node(s) are excluded in this operation.
at org.apache.hadoop.hdfs.server.blockmanagement.BlockManager.chooseTarget4NewBlock(BlockManager.java:1814)
at org.apache.hadoop.hdfs.server.namenode.FSDirWriteFileOp.chooseTargetForNewBlock(FSDirWriteFileOp.java:265)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.getAdditionalBlock(FSNamesystem.java:2563)
at org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.addBlock(NameNodeRpcServer.java:846)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolServerSideTranslatorPB.addBlock(ClientNamenodeProtocolServerSideTranslatorPB .java:510)
at org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos$ClientNamenodeProtocol$2.callBlockingMethod(ClientNamenodeProtoco lProtos.java)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:503)
at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:989)
at org.apache.hadoop.ipc.Server$RpcCall.run(Server.java:871)
at org.apache.hadoop.ipc.Server$RpcCall.run(Server.java:817)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:422)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1889)
at org.apache.hadoop.ipc.Server$Handler.run(Server.java:2606)
at org.apache.hadoop.ipc.Client.getRpcResponse(Client.java:1493)
at org.apache.hadoop.ipc.Client.call(Client.java:1439)
at org.apache.hadoop.ipc.Client.call(Client.java:1349)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:227)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:116)
at com.sun.proxy.$Proxy10.addBlock(Unknown Source)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolTranslatorPB.addBlock(ClientNamenodeProtocolTranslatorPB.java:444)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.apache.hadoop.io.retry.RetryInvocationHandler.invokeMethod(RetryInvocationHandler.java:422)
at org.apache.hadoop.io.retry.RetryInvocationHandler$Call.invokeMethod(RetryInvocationHandler.java:165)
at org.apache.hadoop.io.retry.RetryInvocationHandler$Call.invoke(RetryInvocationHandler.java:157)
at org.apache.hadoop.io.retry.RetryInvocationHandler$Call.invokeOnce(RetryInvocationHandler.java:95)
at org.apache.hadoop.io.retry.RetryInvocationHandler.invoke(RetryInvocationHandler.java:359)
at com.sun.proxy.$Proxy11.addBlock(Unknown Source)
at org.apache.hadoop.hdfs.DataStreamer.locateFollowingBlock(DataStreamer.java:1845)
at org.apache.hadoop.hdfs.DataStreamer.nextBlockOutputStream(DataStreamer.java:1645)
at org.apache.hadoop.hdfs.DataStreamer.run(DataStreamer.java:710)
put: File /input/jn_gaj_lgxx.csv._COPYING_ 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.
报错内容显示的是我的节点没有完全启动成功，但是我jps查看都显示正确，查看磁盘使用情况的时候发现了如下问题：
hadoop dfsadmin -report
解决办法（关闭防火墙，所有节点）如下：
- 查看防火墙状态： systemctl status firewalld
- 关闭防火墙并查看：systemctl stop firewalld（临时关闭）
- 设置默认关闭防火墙：systemctl disable firewalld
再次查看磁盘使用情况显示正常
Configured Capacity: 36477861888 (33.97 GB)
Present Capacity: 26147221672 (24.35 GB)
DFS Remaining: 26146455552 (24.35 GB)
DFS Used: 766120 (748.16 KB)
DFS Used%: 0.00%
Under replicated blocks: 0
Blocks with corrupt replicas: 0
Missing blocks: 0
Missing blocks (with replication factor 1): 0
Pending deletion blocks: 0
-------------------------------------------------
Live datanodes (2):
Name: 172.23.217.104:50010 (slave1)
Hostname: slave1
Decommission Status : Normal
Configured Capacity: 18238930944 (16.99 GB)
DFS Used: 383060 (374.08 KB)
Non DFS Used: 5165164460 (4.81 GB)
DFS Remaining: 13073383424 (12.18 GB)
DFS Used%: 0.00%
DFS Remaining%: 71.68%
Configured Cache Capacity: 0 (0 B)
Cache Used: 0 (0 B)
Cache Remaining: 0 (0 B)
Cache Used%: 100.00%
Cache Remaining%: 0.00%
Xceivers: 1
Last contact: Wed Aug 21 16:03:54 CST 2019
Last Block Report: Wed Aug 21 15:56:36 CST 2019
Name: 172.23.217.105:50010 (slave2)
Hostname: slave2
Decommission Status : Normal
Configured Capacity: 18238930944 (16.99 GB)
DFS Used: 383060 (374.08 KB)
Non DFS Used: 5165475756 (4.81 GB)
DFS Remaining: 13073072128 (12.18 GB)
DFS Used%: 0.00%
DFS Remaining%: 71.68%
Configured Cache Capacity: 0 (0 B)
Cache Used: 0 (0 B)
Cache Remaining: 0 (0 B)
Cache Used%: 100.00%
Cache Remaining%: 0.00%
Xceivers: 1
Last contact: Wed Aug 21 16:03:54 CST 2019
Last Block Report: Wed Aug 21 15:56:36 CST 2019
再次使用hdfs命令上传文件到hdfs，成功！
来源：CSDN
作者：DraGon_HooRay
链接：https://blog.csdn.net/DraGon_HooRay/article/details/103642033