Moving the NameNode to a Different Host
If necessary, you can move the NameNode role instance to a different host machine. For example, the NameNode host may be having hardware problems and you need to move the NameNode to a properly functioning host. Use the instructions in this section to move the NameNode. The host where you want to move the NameNode must be managed by Cloudera Manager.
Adding a New Host
If you need to first add a new host in the cluster, follow the instructions in Adding a Host to the Cluster and then return to this page and proceed to next section below. If you are moving the NameNode to a host machine where you already installed CDH3 and the Cloudera Manager Agent, you can proceed directly to the next section below.
Moving the NameNode Role Instance to a Different Host
To move the NameNode to a different host machine:
- Click the Services tab and then stop all services. For instructions, see Stopping All Services.
- Using the command line, make a backup copy 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. You can view the setting for this property in the HDFS Service > Configuration tab.
- Using the command line, copy the files you backed up from dfs.name.dir directories on the old NameNode host to the new host where you want to run the NameNode.
- In Cloudera Manager, click the Services tab and navigate to the HDFS Service > Instances tab.
- Select the check box next to the NameNode role instance and then click the Delete button. Click Delete again to confirm.
- In the Review configuration changes page that appears, click Skip.
- On the same HDFS Service > Instances tab, click Add to add a NameNode role instance.
- Select the new host where you want to run the NameNode and then click Continue.
- Specify the location of the dfs.name.dir directories where you copied the data on the new host, and then click Accept Changes.
- Click the Services tab and then start all services. For instructions, see Starting All Services. After the HDFS service has started, the Cloudera Manager Server will distribute the new configuration files to the DataNodes which will then be configured with the new IP address of the NameNode.
- Navigate to the HDFS Service > Status tab. The NameNode, Secondary NameNode, and DataNode for the HDFS service should each show a process state of Started, and the overall HDFS service should show a health status of Good.
<< |