Restart multiple components

Use a rolling restart to restart multiple components.

When you restart multiple components, use rolling restarts to distribute the task. A rolling restart stops and then starts multiple running slave components, such as DataNodes, NodeManagers, RegionServers, or Supervisors, using a batch sequence. You set rolling restart parameter values to control the number, time between, tolerance for failures, and limits for restarts of many components across large clusters.

	Important
	Rolling restarts of DataNodes should be performed only during cluster maintenance.

1. In Services, click a service name.
2. In Summary, click a link, such as DataNodes or RegionServers, of any components that you want to restart.
   The Hosts page lists any host names in your cluster on which that component resides.
3. Using the host-level Actions menu, click the name of a slave component option. Then, click Restart.
4. Review and set values for Rolling Restart Parameters.
5. Optionally, reset the flag to restart only components with changed configurations.
6. Click Trigger Rolling Restart.