secondarynamenode异常信息
2012-03-15 16:52:01,150 WARN org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode: Checkpoint Period :3600 secs (60 min)
2012-03-15 16:52:01,151 WARN org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode: Log Size Trigger :67108864 bytes (65536 KB)
2012-03-15 16:57:01,389 ERROR org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode: Exception in doCheckpoint:
2012-03-15 16:57:01,391 ERROR org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode: java.net.ConnectException: Connection refused
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:339)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:198)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:182)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:391)
at java.net.Socket.connect(Socket.java:579)
at java.net.Socket.connect(Socket.java:528)
at sun.net.NetworkClient.doConnect(NetworkClient.java:180)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:388)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:483)
at sun.net.www.http.HttpClient.<init>(HttpClient.java:213)
at sun.net.www.http.HttpClient.New(HttpClient.java:300)
at sun.net.www.http.HttpClient.New(HttpClient.java:316)
at sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(HttpURLConnection.java:992)
at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:928)
at sun.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection.java:846)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1296)
at org.apache.hadoop.hdfs.server.namenode.TransferFsImage.getFileClient(TransferFsImage.java:160)
at org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode$3.run(SecondaryNameNode.java:347)
at org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode$3.run(SecondaryNameNode.java:336)
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:1059)
at org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode.downloadCheckpointFiles(SecondaryNameNode.java:336)
at org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode.doCheckpoint(SecondaryNameNode.java:411)
at org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode.doWork(SecondaryNameNode.java:312)
at org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode.run(SecondaryNameNode.java:275)
at java.lang.Thread.run(Thread.java:722)
原因：
hdfs-site.xml:
<name>dfs.http.address</name>
<value>{your_namenode_ip}:50070</value>
文件中此属性没有配置，second NameNode 无法从NameNode 获取数据。（HTTP的方式获取数据）
此时second NameNode 节点下 ：{hadoop.tmp.di}/dfs/namesecondary/current/ 目录下的数据为空
因为无法完成和NameNode 节点之间的数据同步。