Manage JournalNodes
After enabling NameNode high availability, use the Manage JournalNodes wizards to maintain at least three active JournalNodes.
- NameNode high availability must be enabled in your cluster
-
Click Service Actions, then click Manage
JournalNodes.
-
On Assign JournalNodes, make assignments by clicking the
+ and - icons and selecting host
names in the drop-down menus.
The Assign JournalNodes page enables you to maintain three, current JournalNodes by updating each time you make an assignment. -
On Review, verify the summary of your JournalNode host
assignments and the related configuration changes.
When you are satisfied that all assignments match your intentions, click Next. -
Using a remote shell, complete the steps on Save Namespace.
When you have successfully created a checkpoint, click Next. -
On Add/Remove JournalNodes, monitor the progress bars.
When progress completes, click Next. -
Follow the instructions on Manual Steps Required: Format
JournalNodes.
When JournalNodes have initialized, click Next. -
On Start Active NameNodes, monitor the progress bars.
When all services have re-started, click Next. -
On Manual Steps Required: Bootstrap Standby NameNode,
complete each step, using the instructions on the page.
When you complete the bootstrap steps, click Next. -
On Start All Services, monitor the progress bars.
When the wizard has started all services, click Done. After Ambari Web reloads, you may see some alert notifications. Wait a few minutes until all the services restart and alerts clear.