JobTracker High Availability
The following high availability (HA) features are available for the JobTracker:
- Restart. When a JobTracker service fails, the Warden service on that node attempts to restart the service.
- Failover. If the JobTracker service fails and cannot be restarted by the Warden service on that node, the Zookeeper and Warden services on each node work together to start a new JobTracker service.
- Recovery. After failover occurs, the new JobTracker resumes the tasks that were previously running.
- Discoverability. After failover occurs, Zookeeper directs JobTracker clients to the new JobTracker node.
You can perform the following procedures to manage JobTracker: