hadoop2.5.2 一个master，两个slave，名字分别为slave1和slave2，master启动后如下：
30784 NameNode
31394 Jps
30972 SecondaryNameNode
31132 ResourceManager
slave1和slave2启动后都为如下
8064 Jps
7943 NodeManager
7834 DataNode
感觉没什么异常，然后我在master上执行 hadoop fs -put README.txt /input
一直不动，最后报错
17/03/09 19:59:11 INFO hdfs.DFSClient: Exception in createBlockOutputStream
java.net.ConnectException: Connection timed out
at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:717)
at org.apache.hadoop.net.SocketIOWithTimeout.connect(SocketIOWithTimeout.java:206)
at org.apache.hadoop.net.NetUtils.connect(NetUtils.java:529)
at org.apache.hadoop.hdfs.DFSOutputStream.createSocketForPipeline(DFSOutputStream.java:1526)
at org.apache.hadoop.hdfs.DFSOutputStream$DataStreamer.createBlockOutputStream(DFSOutputStream.java:1328)
at org.apache.hadoop.hdfs.DFSOutputStream$DataStreamer.nextBlockOutputStream(DFSOutputStream.java:1281)
at org.apache.hadoop.hdfs.DFSOutputStream$DataStreamer.run(DFSOutputStream.java:526)
17/03/09 19:59:11 INFO hdfs.DFSClient: Abandoning BP-247473795-10.202.15.17-1489054138763:blk_1073741827_1003
17/03/09 19:59:11 INFO hdfs.DFSClient: Excluding datanode 10.202.15.175:50010
17/03/09 20:01:18 INFO hdfs.DFSClient: Exception in createBlockOutputStream
java.net.ConnectException: Connection timed out
at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:717)
at org.apache.hadoop.net.SocketIOWithTimeout.connect(SocketIOWithTimeout.java:206)
at org.apache.hadoop.net.NetUtils.connect(NetUtils.java:529)
at org.apache.hadoop.hdfs.DFSOutputStream.createSocketForPipeline(DFSOutputStream.java:1526)
at org.apache.hadoop.hdfs.DFSOutputStream$DataStreamer.createBlockOutputStream(DFSOutputStream.java:1328)
at org.apache.hadoop.hdfs.DFSOutputStream$DataStreamer.nextBlockOutputStream(DFSOutputStream.java:1281)
at org.apache.hadoop.hdfs.DFSOutputStream$DataStreamer.run(DFSOutputStream.java:526)
17/03/09 20:01:18 INFO hdfs.DFSClient: Abandoning BP-247473795-10.202.15.17-1489054138763:blk_1073741828_1004
17/03/09 20:01:18 INFO hdfs.DFSClient: Excluding datanode 10.202.15.174:50010
17/03/09 20:01:18 WARN hdfs.DFSClient: DataStreamer Exception
org.apache.hadoop.ipc.RemoteException(java.io.IOException): File /input/README.txt._COPYING_ could only be replicated to 0 nodes instead of minReplication (=1). There are 2 datanode(s) running and 2 node(s) are excluded in this operation.
at org.apache.hadoop.hdfs.server.blockmanagement.BlockManager.chooseTarget(BlockManager.java:1471)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.getAdditionalBlock(FSNamesystem.java:2791)
at org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.addBlock(NameNodeRpcServer.java:606)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolServerSideTranslatorPB.addBlock(ClientNamenodeProtocolServerSideTranslatorPB.java:455)
at org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos$ClientNamenodeProtocol$2.callBlockingMethod(ClientNamenodeProtocolProtos.java)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:585)
at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:928)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2013)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2009)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:422)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1614)
at org.apache.hadoop.ipc.Server$Handler.run(Server.java:2007)
at org.apache.hadoop.ipc.Client.call(Client.java:1411)
at org.apache.hadoop.ipc.Client.call(Client.java:1364)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:206)
at com.sun.proxy.$Proxy9.addBlock(Unknown Source)
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:187)
at org.apache.hadoop.io.retry.RetryInvocationHandler.invoke(RetryInvocationHandler.java:102)
at com.sun.proxy.$Proxy9.addBlock(Unknown Source)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolTranslatorPB.addBlock(ClientNamenodeProtocolTranslatorPB.java:368)
at org.apache.hadoop.hdfs.DFSOutputStream$DataStreamer.locateFollowingBlock(DFSOutputStream.java:1449)
at org.apache.hadoop.hdfs.DFSOutputStream$DataStreamer.nextBlockOutputStream(DFSOutputStream.java:1270)
at org.apache.hadoop.hdfs.DFSOutputStream$DataStreamer.run(DFSOutputStream.java:526)
put: File /input/README.txt._COPYING_ could only be replicated to 0 nodes instead of minReplication (=1). There are 2 datanode(s) running and 2 node(s) are excluded in this operation.
所有的机器都已经关闭了防火墙，也多次删除hadoop.tmp.dir dfs.name.dir dfs.data.dir 对应的文件，并且多次hadoop namenode -format，依然如此，但如果我把 hadoop fs -put README.txt /input 放到slave上执行，不会报错，可以复制过去，三台机器都有这个文件，请各位大神帮忙解答，已经困扰我好几天了。
@cobramonkey谢谢你的回答，现在问题解决了，原因是公司的网络问题，把相关的端口给封了，打开端口就可以了，谢谢
http://blog.csdn.net/renzegis/article/details/40988603
@苏小喵 没用，根据你这个操作还是会报错
题主的问题，个人认为可以试试这样：提示 /input/README.txt._COPYING_ could only be replicated to 0 nodes instead of minReplication (=1)，说明datanode有问题，已被excluded。
可以登录http:本机ip:50070界面中查看Datanode情况，如果这里为空则说明初始化时Datanode是存在问题的，这样虽然jps里有进程但集群里并没有可用的Datanode。或者利用hdfs dfsadmin -report命令检查也可以。如果Datanode缺失，则停止整个集群，之后删除掉你hdfs文件夹下的data、name文件夹下所有内容，清空log日志之后重新初始化hadoop namenode -format再启动集群查看下Datanode的状态，希望有所帮助