最近，要把原来基于Ubuntu下配置的Hadoop集群迁移到RHEL 5下，结果在启动的时候，出现了莫名其妙的问题：

Namenode进程启动起来了，但是在登录到Datanode上启动集群slaves的时候，出现了Datanode无法连接到Namenode的问题，根据Datanode日志，可以很容易地定位到问题，肯定是在集群启动之初，Datanode向Namenode注册的时候失败了，在Datanode端查看异常信息，如下所示：

[plain] view plaincopy
  1. [shirdrn@slave-01 ~]$ tail -500f hadoop/storage/logs/hadoop-shirdrn-datanode-slave-01.log
  2. 2012-02-20 23:54:02,011 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: STARTUP_MSG:
  3. /************************************************************
  4. STARTUP_MSG: Starting DataNode
  5. STARTUP_MSG:   host = slave-01/192.168.0.181
  6. STARTUP_MSG:   args = []
  7. STARTUP_MSG:   version = 0.22.0
  8. STARTUP_MSG:   classpath = /home/shirdrn/hadoop/hadoop-0.22.0/bin/../conf:/home/shirdrn/installation/jdk1.6.0_30/lib/tools.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/..:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-common-0.22.0.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-common-test-0.22.0.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-hdfs-0.22.0.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-hdfs-0.22.0-sources.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-hdfs-ant-0.22.0.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-hdfs-test-0.22.0.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-hdfs-test-0.22.0-sources.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-mapred-0.22.0.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-mapred-0.22.0-sources.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-mapred-examples-0.22.0.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-mapred-test-0.22.0.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-mapred-tools-0.22.0.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/ant-1.6.5.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/ant-1.7.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/ant-launcher-1.7.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/asm-3.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/aspectjrt-1.6.5.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/aspectjtools-1.6.5.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/avro-1.5.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/avro-compiler-1.5.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/avro-ipc-1.5.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-cli-1.2.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-codec-1.4.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-collections-3.2.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-daemon-1.0.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-el-1.0.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-httpclient-3.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-lang-2.5.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-logging-1.1.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-logging-api-1.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-net-1.4.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/core-3.1.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/ecj-3.5.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/guava-r09.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/hsqldb-1.8.0.10.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jackson-core-asl-1.7.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jackson-mapper-asl-1.7.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jasper-compiler-5.5.12.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jasper-runtime-5.5.12.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jdiff-1.0.9.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jets3t-0.7.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jetty-6.1.26.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jetty-util-6.1.26.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jsch-0.1.42.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jsp-2.1-glassfish-2.1.v20091210.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jsp-2.1-jetty-6.1.26.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jsp-api-2.1-glassfish-2.1.v20091210.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/junit-4.8.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/kfs-0.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/log4j-1.2.16.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/mockito-all-1.8.2.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/mockito-all-1.8.5.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/oro-2.0.8.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/paranamer-2.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/paranamer-ant-2.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/paranamer-generator-2.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/qdox-1.12.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/servlet-api-2.5-20081211.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/slf4j-api-1.6.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/slf4j-log4j12-1.6.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/snappy-java-1.0.3.2.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/velocity-1.6.4.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/xmlenc-0.52.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jsp-2.1/*.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/..:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../conf:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-hdfs-0.22.0.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-hdfs-0.22.0-sources.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-hdfs-ant-0.22.0.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-hdfs-test-0.22.0.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-hdfs-test-0.22.0-sources.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/ant-1.6.5.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/ant-1.7.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/ant-launcher-1.7.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/asm-3.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/aspectjrt-1.6.5.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/aspectjtools-1.6.5.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/avro-1.5.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/avro-compiler-1.5.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/avro-ipc-1.5.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-cli-1.2.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-codec-1.4.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-collections-3.2.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-daemon-1.0.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-el-1.0.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-httpclient-3.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-lang-2.5.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-logging-1.1.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-logging-api-1.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-net-1.4.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/core-3.1.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/ecj-3.5.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/guava-r09.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/hsqldb-1.8.0.10.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jackson-core-asl-1.7.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jackson-mapper-asl-1.7.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jasper-compiler-5.5.12.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jasper-runtime-5.5.12.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jdiff-1.0.9.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jets3t-0.7.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jetty-6.1.26.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jetty-util-6.1.26.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jsch-0.1.42.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jsp-2.1-glassfish-2.1.v20091210.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jsp-2.1-jetty-6.1.26.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jsp-api-2.1-glassfish-2.1.v20091210.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/junit-4.8.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/kfs-0.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/log4j-1.2.16.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/mockito-all-1.8.2.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/mockito-all-1.8.5.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/oro-2.0.8.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/paranamer-2.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/paranamer-ant-2.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/paranamer-generator-2.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/qdox-1.12.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/servlet-api-2.5-20081211.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/slf4j-api-1.6.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/slf4j-log4j12-1.6.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/snappy-java-1.0.3.2.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/velocity-1.6.4.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/xmlenc-0.52.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/..:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-hdfs-0.22.0.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-hdfs-0.22.0-sources.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-hdfs-ant-0.22.0.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-hdfs-test-0.22.0.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../hadoop-hdfs-test-0.22.0-sources.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/ant-1.6.5.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/ant-1.7.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/ant-launcher-1.7.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/asm-3.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/aspectjrt-1.6.5.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/aspectjtools-1.6.5.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/avro-1.5.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/avro-compiler-1.5.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/avro-ipc-1.5.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-cli-1.2.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-codec-1.4.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-collections-3.2.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-daemon-1.0.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-el-1.0.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-httpclient-3.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-lang-2.5.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-logging-1.1.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-logging-api-1.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/commons-net-1.4.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/core-3.1.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/ecj-3.5.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/guava-r09.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/hsqldb-1.8.0.10.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jackson-core-asl-1.7.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jackson-mapper-asl-1.7.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jasper-compiler-5.5.12.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jasper-runtime-5.5.12.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jdiff-1.0.9.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jets3t-0.7.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jetty-6.1.26.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jetty-util-6.1.26.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jsch-0.1.42.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jsp-2.1-glassfish-2.1.v20091210.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jsp-2.1-jetty-6.1.26.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/jsp-api-2.1-glassfish-2.1.v20091210.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/junit-4.8.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/kfs-0.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/log4j-1.2.16.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/mockito-all-1.8.2.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/mockito-all-1.8.5.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/oro-2.0.8.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/paranamer-2.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/paranamer-ant-2.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/paranamer-generator-2.3.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/qdox-1.12.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/servlet-api-2.5-20081211.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/slf4j-api-1.6.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/slf4j-log4j12-1.6.1.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/snappy-java-1.0.3.2.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/velocity-1.6.4.jar:/home/shirdrn/hadoop/hadoop-0.22.0/bin/../lib/xmlenc-0.52.jar
  9. STARTUP_MSG:   build = http://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.22/common -r 1207774; compiled by 'jenkins' on Sun Dec  4 00:57:22 UTC 2011
  10. ************************************************************/
  11. 2012-02-20 23:54:02,416 WARN org.apache.hadoop.hdfs.server.common.Util: Path /home/shirdrn/hadoop/storage/data/a should be specified as a URI in configuration files. Please update hdfs configuration.
  12. 2012-02-20 23:54:02,417 WARN org.apache.hadoop.hdfs.server.common.Util: Path /home/shirdrn/hadoop/storage/data/b should be specified as a URI in configuration files. Please update hdfs configuration.
  13. 2012-02-20 23:54:02,417 WARN org.apache.hadoop.hdfs.server.common.Util: Path /home/shirdrn/hadoop/storage/data/c should be specified as a URI in configuration files. Please update hdfs configuration.
  14. 2012-02-20 23:54:03,128 WARN org.apache.hadoop.util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
  15. 2012-02-20 23:54:04,373 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: master/192.168.0.180:9000. Already tried 0 time(s).
  16. 2012-02-20 23:54:05,376 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: master/192.168.0.180:9000. Already tried 1 time(s).
  17. 2012-02-20 23:54:06,379 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: master/192.168.0.180:9000. Already tried 2 time(s).
  18. 2012-02-20 23:54:07,382 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: master/192.168.0.180:9000. Already tried 3 time(s).
  19. 2012-02-20 23:54:08,384 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: master/192.168.0.180:9000. Already tried 4 time(s).
  20. 2012-02-20 23:54:09,385 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: master/192.168.0.180:9000. Already tried 5 time(s).
  21. 2012-02-20 23:54:10,387 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: master/192.168.0.180:9000. Already tried 6 time(s).
  22. 2012-02-20 23:54:11,389 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: master/192.168.0.180:9000. Already tried 7 time(s).
  23. 2012-02-20 23:54:12,426 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: master/192.168.0.180:9000. Already tried 8 time(s).
  24. 2012-02-20 23:54:13,432 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: master/192.168.0.180:9000. Already tried 9 time(s).
  25. 2012-02-20 23:54:13,445 ERROR org.apache.hadoop.hdfs.server.datanode.DataNode: java.io.IOException: Call to master/192.168.0.180:9000 failed on local exception: java.net.NoRouteToHostException: No route to host
  26. at org.apache.hadoop.ipc.Client.wrapException(Client.java:1063)
  27. at org.apache.hadoop.ipc.Client.call(Client.java:1031)
  28. at org.apache.hadoop.ipc.WritableRpcEngine$Invoker.invoke(WritableRpcEngine.java:198)
  29. at $Proxy4.getProtocolVersion(Unknown Source)
  30. at org.apache.hadoop.ipc.WritableRpcEngine.getProxy(WritableRpcEngine.java:235)
  31. at org.apache.hadoop.ipc.RPC.getProxy(RPC.java:275)
  32. at org.apache.hadoop.ipc.RPC.waitForProxy(RPC.java:206)
  33. at org.apache.hadoop.ipc.RPC.waitForProxy(RPC.java:185)
  34. at org.apache.hadoop.ipc.RPC.waitForProxy(RPC.java:169)
  35. at org.apache.hadoop.hdfs.server.datanode.DataNode.<init>(DataNode.java:262)
  36. at org.apache.hadoop.hdfs.server.datanode.DataNode.makeInstance(DataNode.java:1567)
  37. at org.apache.hadoop.hdfs.server.datanode.DataNode.instantiateDataNode(DataNode.java:1510)
  38. at org.apache.hadoop.hdfs.server.datanode.DataNode.createDataNode(DataNode.java:1533)
  39. at org.apache.hadoop.hdfs.server.datanode.DataNode.secureMain(DataNode.java:1680)
  40. at org.apache.hadoop.hdfs.server.datanode.DataNode.main(DataNode.java:1690)
  41. Caused by: java.net.NoRouteToHostException: No route to host
  42. at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
  43. at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:567)
  44. at org.apache.hadoop.net.SocketIOWithTimeout.connect(SocketIOWithTimeout.java:206)
  45. at org.apache.hadoop.net.NetUtils.connect(NetUtils.java:373)
  46. at org.apache.hadoop.ipc.Client$Connection.setupConnection(Client.java:416)
  47. at org.apache.hadoop.ipc.Client$Connection.setupIOstreams(Client.java:504)
  48. at org.apache.hadoop.ipc.Client$Connection.access$2000(Client.java:206)
  49. at org.apache.hadoop.ipc.Client.getConnection(Client.java:1164)
  50. at org.apache.hadoop.ipc.Client.call(Client.java:1008)
  51. ... 13 more
  52. 2012-02-20 23:54:13,447 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: SHUTDOWN_MSG:
  53. /************************************************************
  54. SHUTDOWN_MSG: Shutting down DataNode at slave-01/192.168.0.181
  55. ************************************************************/

首先确定，Namenode的9000端口是否在监听：

[plain] view plaincopy
  1. [shirdrn@master ~]$ netstat -nap | grep 9000
  2. (Not all processes could be identified, non-owned process info
  3. will not be shown, you would have to be root to see it all.)
  4. tcp        0      0 192.168.0.180:9000          0.0.0.0:*                   LISTEN      5374/java

可见，Namenode启动没有问题。

在网上查了一下，有人说（http://hi.baidu.com/tdfrank/blog/item/a1b9e1d95e3b013f10df9b01.html）是，hostname和hosts中配置的虚拟域名不一致会导致出现No route to host异常，经过验证：

master结点：

[plain] view plaincopy
  1. [shirdrn@master ~]$ cat /etc/hosts
  2. # Do not remove the following line, or various programs
  3. # that require network functionality will fail.
  4. 127.0.0.1               localhost localhost
  5. #::1            localhost6.localdomain6 localhost6
  6. 192.168.0.180   master master
  7. 192.168.0.181   slave-01        slave-01
  8. 192.168.0.182   slave-02        slave-02
  9. 192.168.0.183   slave-03        slave-03
  10. [shirdrn@master ~]$ cat /etc/sysconfig/network
  11. NETWORKING=yes
  12. NETWORKING_IPV6=no
  13. HOSTNAME=master

slave-01结点：

[plain] view plaincopy
  1. [shirdrn@slave-01 ~]$ cat /etc/sysconfig/network
  2. NETWORKING=yes
  3. NETWORKING_IPV6=no
  4. HOSTNAME=slave-01
  5. [shirdrn@slave-01 ~]$ cat /etc/hosts
  6. # Do not remove the following line, or various programs
  7. # that require network functionality will fail.
  8. 127.0.0.1               localhost localhost
  9. #::1            localhost6.localdomain6 localhost6
  10. 192.168.0.180   master  master
  11. 192.168.0.181   slave-01        slave-01
  12. 192.168.0.182   slave-02        slave-02
  13. 192.168.0.183   slave-03        slave-03

另外两个从结点也没有问题，此处略去。

经过对比验证，都没有问题。

其实，我已经想到可能是防火墙的问题，经过查证，终于找到了有人曾经遇到过该问题，可见文章http://samwalt.iteye.com/blog/1099348，需要关闭防火墙，在集群中每台机器上都执行如下命令：

[plain] view plaincopy
  1. [shirdrn@master ~]$ su root
  2. Password:
  3. [root@master shirdrn]# service iptables stop
  4. Flushing firewall rules: [  OK  ]
  5. Setting chains to policy ACCEPT: filter [  OK  ]
  6. Unloading iptables modules: [  OK  ]

需要切换到root用户才能执行关闭。

然后，再启动hadoop集群，就没有问题了。

RHEL 5下配置Hadoop集群：java.net.NoRouteToHostException: No route to host问题的解决相关推荐

  1. Windows下安装Cygwin配置Hadoop集群

    Hadoop集群一般是配置到Linux系统之上,如果电脑用的是Windows系统,那么可以通过虚拟机安装Linux系统或者在Windows上安装Cygwin来模拟Linux环境,从而搭建Hadoop集 ...

  2. Linux中安装配置hadoop集群

    原文:http://www.cnblogs.com/lijingchn/p/5574476.html 一. 简介 参考了网上许多教程,最终把hadoop在ubuntu14.04中安装配置成功.下面就把 ...

  3. 学习笔记Hadoop（七）—— Hadoop集群的安装与部署（4）—— 配置Hadoop集群

    四.配置Hadoop集群 Hadoop集群总体规划 Hadoop集群安装采用下面步骤: 在Master节点:上传并解压Hadoop安装包 . 在Master节点:配置Hadoop所需configura ...

  4. 配置hadoop集群常见报错汇总

    配置hadoop集群常见报错汇总 1.使用hdfs namenode -format 格式化报错找不到JAVAHOME 该问题只需在对应的窗口导入JAVAHOME即可,注意,此处为对应环境安装的JDK ...

  5. windows下配置redis集群，启动节点报错：createing server TCP listening socket *:7000:listen:Unknown error...

    windows下配置redis集群,启动节点报错:createing server TCP listening socket *:7000:listen:Unknown error 学习了:https ...

  6. 在windows环境下配置mongoDB集群

    在windows环境下配置mongoDB集群 mongodb官网 官网分片文档 首先感谢这次参考的文章: mongodb搭建高可用分片集群示例-天才卧龙 MongoDB高可用集群搭建示例-lizh 配 ...

  7. java.net.noroute,java.net.NoRouteToHostException: No route to host

    今天重装了服务器的系统之后,重新在两台服务器布署es集群之后,发现es启动报错: [2015-06-16 10:33:33,455][WARN ][transport.netty          ] ...

  8. java.net.NoRouteToHostException: No route to host解决方法

    java.net.NoRouteToHostException: No route to host解决方法 参考文章: (1)java.net.NoRouteToHostException: No r ...

  9. vdbench运行报错：java.net.NoRouteToHostException: No route to host (Host unreachable)

    vdbench运行报错:java.net.NoRouteToHostException: No route to host (Host unreachable) 10:19:13.945 hd2-0 ...

最新文章

  1. 终于能用Google的TPU跑代码了，每小时6.5美元
  2. mysql每日备份_Linux下如何实现Mysql数据库每天自动备份定时备份
  3. VarGFaceNet
  4. halcon的算子清点：Chapter 7 :Image
  5. comment on 视图_oracle 使用comment语句添加表注释
  6. RabbitMQ学习之（二）_Centos6下安装RabbitMQ及管理配置
  7. 利用百度Echarts.js生成雷达图
  8. 数据结构之查找-顺序查找，折半查找，分块查找
  9. 问号匹配，带元组规则的位置匹配不到
  10. html5网页设计作业代码 大学生校园网站制作 学校官网制作html
  11. C语言读取文件函数用法,C语言读取文件流的相关函数用法简介
  12. C++实现费马小定理素数判定法和米勒拉宾素数判定算法生成大素数
  13. 光环python培训
  14. springboot配置logback
  15. JS实现倒计时动画效果
  16. 【转】我在赶集网工作的两个月总结
  17. Github 学习 （整理自http://stormzhang.com/github/2016/06/04/learn-github-from-zero4/ 张哥学Git）
  18. 在VS Code中t把分支写的代码合并到master中并提交到远程仓库github上
  19. python概率编程_Python概率编程库PyMC应用案例二则，pymc应用案例
  20. OSI 模型简单介绍与速记

热门文章

  1. svn图形化控制（svnmanager）
  2. MySQL注释（转）
  3. 通过反射获取私有方法
  4. Failed to execute goal org.apache.maven.plugins:ma
  5. selenium2 webdriver要点理解
  6. AngularJS内置指令 ng-xxx
  7. oracle 用户表、字段信息
  8. C# 邮件类 Mailmessage
  9. 基于Linux的集群系统(五) Linux集群系统的实现
  10. SnagIt的Visual Studio Team System插件