MRS MapReduce

The MRS MapReduce node is used to execute a predefined MapReduce program on MRS.

Table 1 and Table 2 describe the parameters of the MRS MapReduce node.

**Table 1** Parameters of MRS MapReduce nodes
Parameter	Mandatory	Description
Node Name	Yes	Name of a node. The name must contain 1 to 128 characters, including only letters, numbers, underscores (_), hyphens (-), slashes (/), less-than signs (<), and greater-than signs (>).
MRS Cluster Name	Yes	Name of the MRS cluster. To create an MRS cluster, use either of the following methods: Click . On the Clusters page, create an MRS cluster. Go to the MRS console to create an MRS cluster.
MapReduce Job Name	Yes	Name of an MRS job. The name contains 1 to 64 characters, including only letters, digits, and underscores (_). NOTE: The job name cannot contain Chinese characters or more than 64 characters. If the job name does not meet requirements, the MRS job will fail to be submitted.
JAR Package	Yes	Select a JAR package. Before selecting a JAR package, upload the JAR package to the OBS bucket, create a resource on the Manage Resource page, and add the JAR package to the resource management list. For details, see Creating a Resource.
JAR File Parameters	No	Parameters of the JAR package.
Input Data Path	No	Path where the input data resides.
Output Data Path	No	Path where the output data resides.

**Table 2** Advanced parameters
Parameter	Mandatory	Description
Node Status Polling Interval (s)	Yes	Specifies how often the system check completeness of the node task. The value ranges from 1 to 60 seconds.
Max. Node Execution Duration	Yes	Execution timeout interval for the node. If retry is configured and the execution is not complete within the timeout interval, the node will not be retried and is set to the failed state.
Retry upon Failure	Yes	Indicates whether to re-execute a node task if its execution fails. Possible values: Yes: The node task will be re-executed, and the following parameters must be configured: Maximum Retries Retry Interval (seconds) No: The node task will not be re-executed. This is the default setting. NOTE: If Timeout Interval is configured for the node, the node will not be executed again after the execution times out. Instead, the node is set to the failure state.
Failure Policy	Yes	Operation that will be performed if the node task fails to be executed. Possible values: End the current job execution plan: stops running the current job. The job instance status is Failed. Go to the next node: ignores the execution failure of the current node. The job instance status is Failure ignored. Suspend current job execution plan: suspends running the current job. The job instance status is Waiting. Suspend execution plans of the subsequent nodes: stops running subsequent nodes. The job instance status is Failed.