我在这里一步一步地安装hadoophttp://hadoop.apache.org/docs/stable/single_node_setup.html
我用根帐户在redhat中安装hadoop
一切正常，但当./start all并查看日志jobtracker文件时，如下所示：

2013-06-11 08:31:00,194 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: localhost/127.0.0.1:8088. Already tried 8 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
2013-06-11 08:31:01,195 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: localhost/127.0.0.1:8088. Already tried 9 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
2013-06-11 08:31:01,196 ERROR org.apache.hadoop.security.UserGroupInformation: PriviledgedActionException as:root cause:java.net.ConnectException: Call to localhost/127.0.0.1:8088 failed on connection exception: java.net.ConnectException: Connection refused
2013-06-11 08:31:01,196 INFO org.apache.hadoop.mapred.JobTracker: Problem connecting to HDFS Namenode... re-trying
java.net.ConnectException: Call to localhost/127.0.0.1:8088 failed on connection exception: java.net.ConnectException: Connection refused
    at org.apache.hadoop.ipc.Client.wrapException(Client.java:1136)
    at org.apache.hadoop.ipc.Client.call(Client.java:1112)
    at org.apache.hadoop.ipc.RPC$Invoker.invoke(RPC.java:229)
    at com.sun.proxy.$Proxy7.getProtocolVersion(Unknown Source)
    at org.apache.hadoop.ipc.RPC.getProxy(RPC.java:411)
    at org.apache.hadoop.hdfs.DFSClient.createRPCNamenode(DFSClient.java:135)
    at org.apache.hadoop.hdfs.DFSClient.<init>(DFSClient.java:276)
    at org.apache.hadoop.hdfs.DFSClient.<init>(DFSClient.java:241)
    at org.apache.hadoop.hdfs.DistributedFileSystem.initialize(DistributedFileSystem.java:100)
    at org.apache.hadoop.fs.FileSystem.createFileSystem(FileSystem.java:1411)
    at org.apache.hadoop.fs.FileSystem.access$200(FileSystem.java:66)
    at org.apache.hadoop.fs.FileSystem$Cache.get(FileSystem.java:1429)
    at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:254)
    at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:123)
    at org.apache.hadoop.mapred.JobTracker$2.run(JobTracker.java:1908)
    at org.apache.hadoop.mapred.JobTracker$2.run(JobTracker.java:1906)
    at java.security.AccessController.doPrivileged(Native Method)
    at javax.security.auth.Subject.doAs(Subject.java:415)
    at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1149)
    at org.apache.hadoop.mapred.JobTracker.initializeFilesystem(JobTracker.java:1906)
    at org.apache.hadoop.mapred.JobTracker.offerService(JobTracker.java:2324)
    at org.apache.hadoop.mapred.JobTracker.main(JobTracker.java:4792)
Caused by: java.net.ConnectException: Connection refused
    at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
    at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:692)
    at org.apache.hadoop.net.SocketIOWithTimeout.connect(SocketIOWithTimeout.java:206)
    at org.apache.hadoop.net.NetUtils.connect(NetUtils.java:511)
    at org.apache.hadoop.net.NetUtils.connect(NetUtils.java:481)
    at org.apache.hadoop.ipc.Client$Connection.setupConnection(Client.java:453)
    at org.apache.hadoop.ipc.Client$Connection.setupIOstreams(Client.java:579)
    at org.apache.hadoop.ipc.Client$Connection.access$2100(Client.java:202)
    at org.apache.hadoop.ipc.Client.getConnection(Client.java:1243)
    at org.apache.hadoop.ipc.Client.call(Client.java:1087)
    ... 20 more

数据节点的日志如下：

2013-06-11 08:30:25,051 INFO org.apache.hadoop.ipc.RPC: Server at localhost/127.0.0.1:8088 not available yet, Zzzzz...
2013-06-11 08:30:27,052 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: localhost/127.0.0.1:8088. Already tried 0 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
2013-06-11 08:30:28,053 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: localhost/127.0.0.1:8088. Already tried 1 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
2013-06-11 08:30:29,054 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: localhost/127.0.0.1:8088. Already tried 2 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
2013-06-11 08:30:30,055 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: localhost/127.0.0.1:8088. Already tried 3 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
2013-06-11 08:30:31,056 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: localhost/127.0.0.1:8088. Already tried 4 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
2013-06-11 08:30:32,057 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: localhost/127.0.0.1:8088. Already tried 5 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
2013-06-11 08:30:33,058 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: localhost/127.0.0.1:8088. Already tried 6 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
2013-06-11 08:30:34,058 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: localhost/127.0.0.1:8088. Already tried 7 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
2013-06-11 08:30:35,059 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: localhost/127.0.0.1:8088. Already tried 8 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
2013-06-11 08:30:36,060 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: localhost/127.0.0.1:8088. Already tried 9 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
2013-06-11 08:30:36,061 INFO org.apache.hadoop.ipc.RPC: Server at localhost/127.0.0.1:8088 not available yet, Zzzzz...

我的配置xml

<configuration>
     <property>
         <name>fs.default.name</name>
         <value>hdfs://127.0.0.1:8088</value>
     </property>
</configuration>

<configuration>
     <property>
         <name>mapred.job.tracker</name>
         <value>127.0.0.1:8089</value>
     </property>
</configuration>

<configuration>
     <property>
         <name>dfs.replication</name>
         <value>1</value>
     </property>
</configuration>

我的hots文件：

192.168.1.211   kkapps  # Added by NetworkManager
127.0.0.1  localhost
::1        localhost

谢谢你的调查！