masters日志：
java.io.IOException: File /home/wangzhengqi/tmp/mapred/system/jobtracker.info could only be replicated to 0 nodes, instead of 1
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.getAdditionalBlock(FSNamesystem.java:1920)
at org.apache.hadoop.hdfs.server.namenode.NameNode.addBlock(NameNode.java:783)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:587)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:1432)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:1428)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:415)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1190)
at org.apache.hadoop.ipc.Server$Handler.run(Server.java:1426)
slaves日志：2015-04-19 11:19:45,137 INFO org.apache.hadoop.ipc.RPC: Server at ubuntu-2/192.168.128.129:9000 not available yet, Zzzzz...
查看任务：
masters:
root@ubuntu-2:/usr/hadoop/conf# jps
2897 TaskTracker
2386 DataNode
2177 NameNode
2603 SecondaryNameNode
2940 Jps
2684 JobTracker
root@ubuntu-2:/usr/hadoop/conf# hadoop dfsadmin -report
Configured Capacity: 20334034944 (18.94 GB)
Present Capacity: 14065430543 (13.1 GB)
DFS Remaining: 14065401856 (13.1 GB)
DFS Used: 28687 (28.01 KB)
DFS Used%: 0%
Under replicated blocks: 1(这里应该是3台才对， 因为我还有两台子节点)
Blocks with corrupt replicas: 0
Missing blocks: 0
slaves1:[root@centos-4 conf]# jps
1288 Jps
1163 DataNode
1225 TaskTracker
slaves2:[root@centos-3 conf]# jps
1288 Jps
1163 DataNode
1225 TaskTracker
start-all.sh后：
两台子节点的datanode都 已经启动了， 就是链接 不上namenode,,
这到底是怎么回事， 请大神解答！！！1
