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Amazon Elastic MapReduce
API Reference (API Version 2009-03-31)

ListInstanceGroups

Provides all available details about the instance groups in a cluster.

Request Syntax

{
   "ClusterId": "string",
   "Marker": "string"
}

Request Parameters

For information about the parameters that are common to all actions, see Common Parameters.

The request accepts the following data in JSON format.

ClusterId

The identifier of the cluster for which to list the instance groups.

Type: String

Required: Yes

Marker

The pagination token that indicates the next set of results to retrieve.

Type: String

Required: No

Response Syntax

{
   "InstanceGroups": [ 
      { 
         "AutoScalingPolicy": { 
            "Constraints": { 
               "MaxCapacity": number,
               "MinCapacity": number
            },
            "Rules": [ 
               { 
                  "Action": { 
                     "Market": "string",
                     "SimpleScalingPolicyConfiguration": { 
                        "AdjustmentType": "string",
                        "CoolDown": number,
                        "ScalingAdjustment": number
                     }
                  },
                  "Description": "string",
                  "Name": "string",
                  "Trigger": { 
                     "CloudWatchAlarmDefinition": { 
                        "ComparisonOperator": "string",
                        "Dimensions": [ 
                           { 
                              "Key": "string",
                              "Value": "string"
                           }
                        ],
                        "EvaluationPeriods": number,
                        "MetricName": "string",
                        "Namespace": "string",
                        "Period": number,
                        "Statistic": "string",
                        "Threshold": number,
                        "Unit": "string"
                     }
                  }
               }
            ],
            "Status": { 
               "State": "string",
               "StateChangeReason": { 
                  "Code": "string",
                  "Message": "string"
               }
            }
         },
         "BidPrice": "string",
         "Configurations": [ 
            { 
               "Classification": "string",
               "Configurations": [ 
                  "Configuration"
               ],
               "Properties": { 
                  "string" : "string" 
               }
            }
         ],
         "EbsBlockDevices": [ 
            { 
               "Device": "string",
               "VolumeSpecification": { 
                  "Iops": number,
                  "SizeInGB": number,
                  "VolumeType": "string"
               }
            }
         ],
         "EbsOptimized": boolean,
         "Id": "string",
         "InstanceGroupType": "string",
         "InstanceType": "string",
         "Market": "string",
         "Name": "string",
         "RequestedInstanceCount": number,
         "RunningInstanceCount": number,
         "ShrinkPolicy": { 
            "DecommissionTimeout": number,
            "InstanceResizePolicy": { 
               "InstancesToProtect": [ "string" ],
               "InstancesToTerminate": [ "string" ],
               "InstanceTerminationTimeout": number
            }
         },
         "Status": { 
            "State": "string",
            "StateChangeReason": { 
               "Code": "string",
               "Message": "string"
            },
            "Timeline": { 
               "CreationDateTime": number,
               "EndDateTime": number,
               "ReadyDateTime": number
            }
         }
      }
   ],
   "Marker": "string"
}

Response Elements

If the action is successful, the service sends back an HTTP 200 response.

The following data is returned in JSON format by the service.

InstanceGroups

The list of instance groups for the cluster and given filters.

Type: Array of InstanceGroup objects

Marker

The pagination token that indicates the next set of results to retrieve.

Type: String

Errors

For information about the errors that are common to all actions, see Common Errors.

InternalServerException

This exception occurs when there is an internal failure in the EMR service.

HTTP Status Code: 500

InvalidRequestException

This exception occurs when there is something wrong with user input.

HTTP Status Code: 400

See Also

For more information about using this API in one of the language-specific AWS SDKs, see the following: