Its good to take backup of existing data storage (namenode & secondary namenode). Konstantine has explained the steps in this JIRA https://issues.apache.org/jira/browse/HADOOP-2585?focusedCommentId=12558173#action_12558173
HTH, Lohit ----- Original Message ---- From: Stu Hood <[EMAIL PROTECTED]> To: [email protected] Sent: Monday, October 13, 2008 12:11:29 AM Subject: Urgent: Need -importCheckpoint equivalent for 0.15.3 We're running Hadoop 0.15.3 (yes, time for an upgrade), and for the first time, we need to have our secondary namenode take over for our failed namenode. There may not be an equivalent command to `namenode -importCheckpoint` in Hadoop 0.15.3, but I need to know the proper way to restore from a checkpoint, in case our namenode cannot be recovered. Thanks, Stu Hood Architecture Software Developer Mailtrust, a Division of Rackspace
