This is the documentation for Cloudera Manager 5.1.x. Documentation for other versions is available at Cloudera Documentation.

NameNodes

Required Role:

Formatting the NameNode and Creating the /tmp Directory

When you add an HDFS service, the wizard automatically formats the NameNode and creates the /tmp directory on HDFS. If you quit the wizard or it does not finish, you can format the NameNode and create the /tmp directory outside the wizard by doing these steps:

  1. Stop the HDFS service if it is running. See Starting, Stopping, and Restarting Services.
  2. In the HDFS > Instances tab, click the NameNode role instance.
  3. Select Actions > Format.
  4. In the HDFS > Instances tab, click the NameNode role instance.
  5. Select Actions > Create /tmp Directory.
  6. Start the HDFS service.

Moving the NameNode to a Different Host

If the NameNode host has hardware problems and you need to move the NameNode to another host, you can do so as follows:
  1. If the host to which you want to move the NameNode is not in the cluster, follow the instructions in Adding a Host to the Cluster to add the host.
  2. Stop all cluster services.
  3. Make a backup of the dfs.name.dir directories on the existing NameNode host. Make sure you back up the fsimage and edits files. They should be the same across all of the directories specified by the dfs.name.dir property.
  4. Copy the files you backed up from dfs.name.dir directories on the old NameNode host to the host where you want to run the NameNode.
  5. Go to the HDFS service.
  6. Click the Instances tab.
  7. Select the checkbox next to the NameNode role instance and then click the Delete button. Click Delete again to confirm.
  8. In the Review configuration changes page that appears, click Skip.
  9. Click Add Role Instances to add a NameNode role instance.
  10. Select the host where you want to run the NameNode and then click Continue.
  11. Specify the location of the dfs.name.dir directories where you copied the data on the new host, and then click Accept Changes.
  12. Start cluster services. After the HDFS service has started, Cloudera Manager distributes the new configuration files to the DataNodes, which will be configured with the IP address of the new NameNode host.
  13. Go to the HDFS service. The NameNode, Secondary NameNode, and DataNode roles should each show a process state of Started, and the HDFS service should show a status of Good.
Page generated September 3, 2015.