the log is:
2012-12-17 17:09:05,646 ERROR org.apache.hadoop.hdfs.server.namenode.NameNode: java.lang.NullPointerException
        at org.apache.hadoop.hdfs.server.namenode.FSDirectory.addChild(FSDirectory.java:1094)
        at org.apache.hadoop.hdfs.server.namenode.FSDirectory.addChild(FSDirectory.java:1106)
        at org.apache.hadoop.hdfs.server.namenode.FSDirectory.addNode(FSDirectory.java:1009)
        at org.apache.hadoop.hdfs.server.namenode.FSDirectory.unprotectedAddFile(FSDirectory.java:208)
        at org.apache.hadoop.hdfs.server.namenode.FSEditLog.loadFSEdits(FSEditLog.java:626)
        at org.apache.hadoop.hdfs.server.namenode.FSImage.loadFSEdits(FSImage.java:1015)
        at org.apache.hadoop.hdfs.server.namenode.FSImage.loadFSImage(FSImage.java:833)
        at org.apache.hadoop.hdfs.server.namenode.FSImage.recoverTransitionRead(FSImage.java:372)
        at org.apache.hadoop.hdfs.server.namenode.FSDirectory.loadFSImage(FSDirectory.java:100)
        at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.initialize(FSNamesystem.java:388)
        at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.<init>(FSNamesystem.java:362)
        at org.apache.hadoop.hdfs.server.namenode.NameNode.initialize(NameNode.java:276)
        at org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:496)
        at org.apache.hadoop.hdfs.server.namenode.NameNode.createNameNode(NameNode.java:1279)
        at org.apache.hadoop.hdfs.server.namenode.NameNode.main(NameNode.java:1288)

core-site.xml:
<configuration>
<property>
<name>fs.default.name</name>
<value>hdfs://h46:9000</value>
</property>
<property>
<name>hadoop.tmp.dir</name>
<value>/home/hbase/hadoopdata/tmp</value>
</property>
<property>
<name>dfs.hosts.exclude</name>
<value>/home/hbase/hadoop/conf/dfs.hosts.exclude</value>
</property>
<property>
<name>local.cache.size</name>
<value>10737418240</value>
<description>10G</description>
</property>
</configuration>

hdfs-site.xml
<configuration>
<property>
  <name>dfs.name.dir</name>
  <value>/home/hbase/hadoopdata/name</value>
</property>
<property>
  <name>dfs.data.dir</name>
  <value>/home/hbase/hadoopdata/data/data</value>
</property>
<property>
...
</configuration>

mapred-site.xml
<configuration>
<property>
<name>mapred.job.tracker</name>
<value>h46:9001</value>
</property>
<property>
<name>mapred.local.dir</name>
<value>/home/hbase/hadoopdata/mapred/local</value>
</property>
<property>
<name>mapred.system.dir</name>
<value>/home/hbase/hadoopdata/mapred/system</value>
</property>
...
</configuration>

hbase-site.xml
<configuration>
<property>
  <name>hbase.rootdir</name>
  <value>hdfs://h46:9000/hbase</value>
</property>
<property>
  <name>hbase.cluster.distributed</name>
  <value>true</value>
</property>
<property>
  <name>hbase.zookeeper.quorum</name>
  <value>h46,h47,h48</value>
</property>
<property>
  <name>hbase.zookeeper.property.dataDir</name>
  <value>/home/hbase/hadoopdata/zookeeper</value>
</property>
<property>
  <name>zookeeper.session.timeout</name>
  <value>90000</value>
</property>
...
</configuration>

this problem maybe caused by us to change ips of the system.
I write "edits" with  0xffffffeeff, then the name node cound start up, but hbase can't list table.


[hbase@h46 ~]$ hadoop fsck /
...
The filesystem under path ‘/’ is CORRUPT

I removed  many tables by "hadoop fs -rmr", so i can list table names,but when i scan table,it didn't return.
I don't know why there are so many corrupts. the .META. and -ROOT- table are all corrupt.

we backup name node by 3 ways. the second name node; the nfs namenode in different node; and name node it's self. but they all didn't work,because all fs image and edits files  are polluted by error data of the name node.
I think hadoop should back up namenode by different directory with date or time. It's important to remain logs to history.  

if some one need this tool to backup name node daily in different directory, I should write one. 

thank you ,Mohammad 

Andy
2012/12/17 Mohammad Tariq <dontariq@gmail.com>
Hello Andy,

         Can I have a look at the NameNode logs?Also paste your config files.

Best Regards,
Tariq



On Mon, Dec 17, 2012 at 3:21 PM, 周梦想 <ablozhou@gmail.com> wrote:
Andy