正常啟動Hadoop之後發現NameNode和jobtracker自動關閉，檢視日誌後發現出現如下的問題：

 2014-04-29 11:49:12,756 INFO org.apache.hadoop.hdfs.server.namenode.DecommissionManager: Interrupted Monitor
 55 java.lang.InterruptedException: sleep interrupted
 56     at java.lang.Thread.sleep(Native Method)
 57     at org.apache.hadoop.hdfs.server.namenode.DecommissionManager$Monitor.run(DecommissionManager.java:65)
 58     at java.lang.Thread.run(Thread.java:722)
 59 2014-04-29 11:49:12,758 ERROR org.apache.hadoop.hdfs.server.namenode.NameNode: java.net.BindException: Problem binding to frontend.local/10.1.1.1:9000 : Cannot assi    gn requested address
 60     at org.apache.hadoop.ipc.Server.bind(Server.java:228)
 61     at org.apache.hadoop.ipc.Server$Listener.<init>(Server.java:302)
 62     at org.apache.hadoop.ipc.Server.<init>(Server.java:1488)
 63     at org.apache.hadoop.ipc.RPC$Server.<init>(RPC.java:560)
 64     at org.apache.hadoop.ipc.RPC.getServer(RPC.java:521)
 65     at org.apache.hadoop.hdfs.server.namenode.NameNode.initialize(NameNode.java:302)
 66     at org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:536)
 67     at org.apache.hadoop.hdfs.server.namenode.NameNode.createNameNode(NameNode.java:1410)
 68     at org.apache.hadoop.hdfs.server.namenode.NameNode.main(NameNode.java:1419)
 69 Caused by: java.net.BindException: Cannot assign requested address
 70     at sun.nio.ch.Net.bind0(Native Method)
 71     at sun.nio.ch.Net.bind(Net.java:344)
 72     at sun.nio.ch.Net.bind(Net.java:336)
 73     at sun.nio.ch.ServerSocketChannelImpl.bind(ServerSocketChannelImpl.java:199)
 74     at sun.nio.ch.ServerSocketAdaptor.bind(ServerSocketAdaptor.java:74)
 75     at org.apache.hadoop.ipc.Server.bind(Server.java:226)
 76     ... 8 more

經過仔細的查詢之後發現時因為防火牆的問題，因為啟動了iptables

解決方法：

如果是Ubuntu，Ubuntu裡iptables不是一個service，所以不能使用service iptables stop命令。可以使用apt-get remove iptables把它解除安裝掉