我正在尝试在 EC2 实例上设置 Hadoop 集群（CDH4）。当我尝试对其进行格式化时，名称节点不断崩溃。这是我得到的错误。
2013-04-12 05:37:16,995 FATAL org.apache.hadoop.hdfs.server.namenode.NameNode: Exception in namenode join
java.net.BindException: Problem binding to [head.node.iec.project:8020] java.net.BindException: Cannot assign requested address; For more details see: http://wiki.apache.org/hadoop/BindException
at org.apache.hadoop.net.NetUtils.wrapException(NetUtils.java:715)
at org.apache.hadoop.ipc.Server.bind(Server.java:356)
at org.apache.hadoop.ipc.Server$Listener.<init>(Server.java:454)
at org.apache.hadoop.ipc.Server.<init>(Server.java:1835)
at org.apache.hadoop.ipc.RPC$Server.<init>(RPC.java:970)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Server.<init>(ProtobufRpcEngine.java:375)
at org.apache.hadoop.ipc.ProtobufRpcEngine.getServer(ProtobufRpcEngine.java:350)
at org.apache.hadoop.ipc.RPC.getServer(RPC.java:695)
at org.apache.hadoop.ipc.RPC.getServer(RPC.java:684)
at org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.<init>(NameNodeRpcServer.java:239)
at org.apache.hadoop.hdfs.server.namenode.NameNode.createRpcServer(NameNode.java:453)
at org.apache.hadoop.hdfs.server.namenode.NameNode.initialize(NameNode.java:435)
at org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:609)
at org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:590)
at org.apache.hadoop.hdfs.server.namenode.NameNode.createNameNode(NameNode.java:1141)
at org.apache.hadoop.hdfs.server.namenode.NameNode.main(NameNode.java:1205)
2013-04-12 05:37:16,998 INFO org.apache.hadoop.util.ExitUtil: Exiting with status 1
2013-04-12 05:37:17,024 INFO org.apache.hadoop.hdfs.server.namenode.NameNode: SHUTDOWN_MSG:
主机文件看起来像这样
127.0.0.1 localhost
184.73.62.190 head.node.iec.project head
54.244.75.141 node1.node.iec.project node1
# The following lines are desirable for IPv6 capable hosts
::1 ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
ff02::3 ip6-allhosts
有人可以帮我弄这个吗？