Secondarynamenode无法正常备份:ERROR org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode: Exception in doCheckpoint

原先使用hadoop默认设置（hadoop1.2.1），secondarynamenode会正常进行备份，定时从namenode拷贝image文件到SNN。但是具体SNN备份的时间周期和log文件的大小无法定制，后来楼主就修改了SNN的设置，将fs.checkpoint.period修改为3600s,fs.checkpoint.size修改为64兆。在core-site.xml配置文件中添加这两个参数之后，却发现SNN总是无法备份。后来google查找发现还是配置文件没有配置完整造成的，修改配置文件core-site.xml 和hdfs-site.xml文件后问题解决。

贴一下这两个文件内容：

core-site.xml：

 1 <!-- ****************************************************************************************-->
 2 <!-- This file only used in secondnamenode!!-->
 3 <!-- ****************************************************************************************-->
 4 
 5 <configuration>
 6 
 7 <property>
 8         <name>hadoop.tmp.dir</name>
 9         <value>/bigdata/hadoop/tmp/</value>
10         <description>A base for other temporary directories.</description>
11 </property>
12 
13 <property>
14         <name>fs.default.name</name>
15         <value>hdfs://namenode:54310</value>
16 </property>
17 
18 <property>
19         <name>fs.checkpoint.period</name>
20         <value>3600</value>
21         <description>The number of seconds between two periodic checkpoints. </description>
22 </property>
23 
24 <property>
25         <name>fs.checkpoint.size</name>
26         <value>67108864</value>
27         <description>The size of the current edit log (in bytes) that triggers a periodic checkpoint even if the fs.checkpoint.period hasn't
28 expired. </description>
29 </property>
30 
31 
32 <property>
33         <name>fs.checkpoint.dir</name>
34         <value>/bigdata/hadoop/namesecondary/</value>
35 </property>
36 </configuration>

hdfs-site.xml

 1 <!-- ****************************************************************************************-->
 2 <!-- This file only used in secondnamenode!!-->
 3 <!-- ****************************************************************************************-->
 4 
 5 <configuration>
 6 
 7 
 8 <property>
 9         <name>fs.checkpoint.period</name>
10         <value>3600</value>
11         <description>The number of seconds between two periodic checkpoints. </description>
12 </property>
13 
14 
15 <property>
16        <name>dfs.secondary.http.address</name>
17        <value>secondnamenode:50090</value>
18 </property>
19 
20 
21 <property>
22      <name>dfs.http.address</name>
23      <value>namenode:50070</value>
24      <final>true</final>
25 </property>
26 
27 
28 <property>
29         <name>dfs.replication</name>
30         <value>2</value>
31 </property>
32 
33 <property>
34         <name>dfs.name.dir</name>
35         <value>/bigdata/hadoop/secondnamenodelogs/</value>
36 </property>
......

其中红色部分为关键参数。楼主刚开始以为hdfs-site.xml不需要做修改，后来发现问题主要是出现在这个文件中，真是坑爹@！！！

在hdfs-site.xml文件中需要加上core-site.xml文件中的参数fs.checkpoint.period 或者fs.checkpoint.size；dfs.http.address指定namenode的访问地址，SNN根据这个地址来获取NN保存的image。dfs.secondary.http.address则是SNN自己Web接口，这个参数必须配置，楼主就是因为没有配置这个参数一直报下面这个错误：

 1 2014-06-25 14:17:40,408 ERROR org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode: Exception in doCheckpoint:
 2 2014-06-25 14:17:40,408 ERROR org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode: java.io.FileNotFoundException: http://namenode:50070/
 3 getimage?putimage=1&port=50090&machine=0.0.0.0&token=-41:620270652:0:1403579817000:1403578915285&newChecksum=7fcdd4793ce44f017d290e7db78870e7
 4         at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1434)
 5         at org.apache.hadoop.hdfs.server.namenode.TransferFsImage.getFileClient(TransferFsImage.java:177)
 6         at org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode.putFSImage(SecondaryNameNode.java:462)
 7         at org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode.doCheckpoint(SecondaryNameNode.java:525)
 8         at org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode.doWork(SecondaryNameNode.java:396)
 9         at org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode.run(SecondaryNameNode.java:360)
10         at java.lang.Thread.run(Thread.java:662)