Sometimes the metadata gets corrupted. Its happened with me on multiple occasions during the initial stages of setting up the cluster. What I did was simply delete the entire directory where the metadata and the actual data is being stored by hdfs. Since I was playing around with the systems and didnt care much about the data, I could do so. If it doesnt spoil anything for you, go ahead and try it. It might work.
Secondly, you've specified the dfs.data.dir parameter but havent specified the metadata directory. AFAIK, it will take /tmp as the default. Since /tmp gets cleaned up, you'll lose your metadata and that could be causing the system to not come up. Specify that parameter in the config file. Amandeep Amandeep Khurana Computer Science Graduate Student University of California, Santa Cruz On Fri, Jun 26, 2009 at 2:33 PM, Boyu Zhang <boyuzhan...@gmail.com> wrote: > Matt, > > Thanks a lot for your reply! I did formatted the namenode. But I got the > same error again. And actually I successfully run the example jar file > once, > but after that one time, I couldn't get it run again. I clean the /tmp dir > every time before I format namenode again(I am just testing it, so I don't > worry about losing data:). Still, I got the same error when I execute the > bin/start-dfs.sh . I checked my conf, and I can't figure out why. Here is > my > conf file: > > I really appreciate if you could take a look at it. Thanks a lot. > > > <configuration> > > <property> > <name>fs.default.name</name> > <value>hdfs://hostname1:9000</value> > </property> > > > <property> > <name>mapred.job.tracker</name> > <value>hostname2:9001</value> > </property> > > > > <property> > <name>dfs.data.dir</name> > <value>/data/zhang/hadoop/dfs/data</value> > <description>Determines where on the local filesystem an DFS data node > should store its blocks. If this is a comma-delimited > list of directories, then data will be stored in all named > directories, typically on different devices. > Directories that do not exist are ignored. > </description> > </property> > > > <property> > <name>mapred.local.dir</name> > <value>/data/zhang/hadoop/mapred/local</value> > <description>The local directory where MapReduce stores intermediate > data files. May be a comma-separated list of > directories on different devices in order to spread disk i/o. > Directories that do not exist are ignored. > </description> > </property> > </configuration> > > > -----Original Message----- > From: Matt Massie [mailto:m...@cloudera.com] > Sent: Friday, June 26, 2009 4:31 PM > To: core-user@hadoop.apache.org > Subject: Re: Error in Cluster Startup: NameNode is not formatted > > Boyu- > > You didn't do anything stupid. I've forgotten to format a NameNode > too myself. > > If you check the QuickStart guide at > http://hadoop.apache.org/core/docs/current/quickstart.html > you'll see that formatting the NameNode is the first of the > Execution section (near the bottom of the page). > > The command to format the NameNode is: > > hadoop namenode -format > > A warning though, you should only format your NameNode once. Just > like formatting any filesystem, you can loss data if you (re)format. > > Good luck. > > -Matt > > On Jun 26, 2009, at 1:25 PM, Boyu Zhang wrote: > > > Hi all, > > > > I am a student and I am trying to install the Hadoop on a cluster, I > > have > > one machine running namenode, one running jobtracker, two slaves. > > > > When I run the /bin/start-dfs.sh , there is something wrong with my > > namenode, it won't start. Here is the error message in the log file: > > > > ERROR org.apache.hadoop.fs.FSNamesystem: FSNamesystem initialization > > failed. > > java.io.IOException: NameNode is not formatted. > > at > > org.apache.hadoop.dfs.FSImage.recoverTransitionRead(FSImage.java:243) > > at > > org.apache.hadoop.dfs.FSDirectory.loadFSImage(FSDirectory.java:80) > > at > > org.apache.hadoop.dfs.FSNamesystem.initialize(FSNamesystem.java:294) > > at > > org.apache.hadoop.dfs.FSNamesystem.<init>(FSNamesystem.java:273) > > at org.apache.hadoop.dfs.NameNode.initialize(NameNode.java:148) > > at org.apache.hadoop.dfs.NameNode.<init>(NameNode.java:193) > > at org.apache.hadoop.dfs.NameNode.<init>(NameNode.java:179) > > at > > org.apache.hadoop.dfs.NameNode.createNameNode(NameNode.java:830) > > at org.apache.hadoop.dfs.NameNode.main(NameNode.java:839) > > > > > > I think it is something stupid i did, could somebody help me out? > > Thanks a > > lot! > > > > > > Sincerely, > > > > Boyu Zhang > > >
