hello,

I encountered a problem of hadoop 1.02. At begining, the second name node
exited and can't start,it reports error like below:

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)

then, i shut down all process,but the name node also can't start up, and
reported the same error.
I consider the edits or edits.new may be corrupted, any one could give me
some advice?
including how to repair edits manually?

Thanks!

Andy zhou

Hello Andy,

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

Best Regards,
Tariq
+91-9741563634

On Mon, Dec 17, 2012 at 3:21 PM, 周梦想 <[EMAIL PROTECTED]> wrote:

> Andy

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 <[EMAIL PROTECTED]>