Hi Abhay What is the value for hadoop.tmp.dir or dfs.name.dir . If it was set to /tmp the contents would be deleted on a OS restart. You need to change this location before you start your NN. Regards Bejoy KS
Sent from handheld, please excuse typos. -----Original Message----- From: Abhay Ratnaparkhi <[email protected]> Date: Fri, 24 Aug 2012 12:58:41 To: <[email protected]> Reply-To: [email protected] Subject: namenode not starting Hello, I had a running hadoop cluster. I restarted it and after that namenode is unable to start. I am getting error saying that it's not formatted. :( Is it possible to recover the data on HDFS? 2012-08-24 03:17:55,378 ERROR org.apache.hadoop.hdfs.server.namenode.FSNamesystem: FSNamesystem initialization failed. java.io.IOException: NameNode is not formatted. at org.apache.hadoop.hdfs.server.namenode.FSImage.recoverTransitionRead(FSImage.java:434) at org.apache.hadoop.hdfs.server.namenode.FSDirectory.loadFSImage(FSDirectory.java:110) at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.initialize(FSNamesystem.java:291) at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.<init>(FSNamesystem.java:270) at org.apache.hadoop.hdfs.server.namenode.NameNode.loadNamesystem(NameNode.java:271) at org.apache.hadoop.hdfs.server.namenode.NameNode.initialize(NameNode.java:303) at org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:433) at org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:421) at org.apache.hadoop.hdfs.server.namenode.NameNode.createNameNode(NameNode.java:1359) at org.apache.hadoop.hdfs.server.namenode.NameNode.main(NameNode.java:1368) 2012-08-24 03:17:55,380 ERROR org.apache.hadoop.hdfs.server.namenode.NameNode: java.io.IOException: NameNode is not formatted. at org.apache.hadoop.hdfs.server.namenode.FSImage.recoverTransitionRead(FSImage.java:434) at org.apache.hadoop.hdfs.server.namenode.FSDirectory.loadFSImage(FSDirectory.java:110) at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.initialize(FSNamesystem.java:291) at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.<init>(FSNamesystem.java:270) at org.apache.hadoop.hdfs.server.namenode.NameNode.loadNamesystem(NameNode.java:271) at org.apache.hadoop.hdfs.server.namenode.NameNode.initialize(NameNode.java:303) at org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:433) at org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:421) at org.apache.hadoop.hdfs.server.namenode.NameNode.createNameNode(NameNode.java:1359) at org.apache.hadoop.hdfs.server.namenode.NameNode.main(NameNode.java:1368) Regards, Abhay
