After you modify the configuration items of a service, you must restart the service for the modifications to take effect. If a service is faulty or abnormal, you can try to restore the service by restarting the service.
Prerequisites
An E-MapReduce (EMR) cluster is created. For more information, see Create a cluster.
Precautions
To minimize impacts on business operations, we recommend that you restart a service in rolling mode. For instances deployed in primary/secondary mode, restart the service on the secondary instance and then the service on the primary instance.
Restarting a service is not the same as restarting a cluster. EMR does not allow you to restart a cluster.
You can perform the following operations to manually terminate a restart operation on a service: In the upper-right corner of the Services tab, click Operation History. In the Operation History panel, find the desired operation and click Terminate in the Actions column. If you terminate a restart operation on a service, the configuration of nodes in a node group may be inconsistent.
Procedure
Go to the Services tab.
Log on to the EMR console. In the left-side navigation pane, click EMR on ECS.
In the top navigation bar, select the region in which your cluster resides and select a resource group based on your business requirements.
On the EMR on ECS page, find the desired cluster and click Services in the Actions column.
On the Services tab, find the service that you want to restart, move the pointer over the
icon, and then select Restart. Alternatively, go to the Configure tab of the service. In the upper-right corner of the Configure tab, choose .
In the dialog box that appears, configure the Execution Reason parameter and click OK.
The following table describes the parameters that you can configure.
Parameter
Description
Rolling Execution
The switch is turned on by default. If the switch is turned on, the system runs tasks at the interval specified in Rolling Execution Interval. The Rolling Execution Interval parameter specifies the interval between two executions of a task.
ImportantIf you turn off the switch, the service is restarted on all nodes at the same time. As a result, the service becomes unavailable during the restart. Proceed with caution.
Failure Handling Policy
Proceed Upon Failure of Single Node: When the system runs a task, if a node fails to pass the check, the system runs the task on other healthy nodes.
Stop Upon Failure of Single Node: When the system runs a task, if a node fails to pass the check, the system terminates the task.
Execution Reason
The execution reason.
In the Confirm message, click OK.
Then, the system prompts The operation is successful.. The system will run the task based on the policy that you configured.
References
For information about how to view the health status of a service and its components, see View the health status of services and components.
For information about service-related issues, see FAQ about cluster management.