DescribeScalingRules - Auto Scaling - Alibaba Cloud Documentation Center

Queries scaling rules. When you call this operation, you can specify the ID, name, or Alibaba Cloud Resource Name (ARN) of a scaling rule to query the details of the scaling rule. For example, you can query the adjustment method, instance warm-up period, and associated event-triggered tasks of the desired scaling rule.

Operation description

You can specify a scaling group ID to query all scaling rules in the scaling group. You can also specify the scaling rule ID, name, unique identifier, and type in the request parameters as filter conditions.

Debugging

You can run this interface directly in OpenAPI Explorer, saving you the trouble of calculating signatures. After running successfully, OpenAPI Explorer can automatically generate SDK code samples.

Debug

Authorization information

The following table shows the authorization information corresponding to the API. The authorization information can be used in the Action policy element to grant a RAM user or RAM role the permissions to call this API operation. Description:

Operation: the value that you can use in the Action element to specify the operation on a resource.
Access level: the access level of each operation. The levels are read, write, and list.
Resource type: the type of the resource on which you can authorize the RAM user or the RAM role to perform the operation. Take note of the following items:
- The required resource types are displayed in bold characters.
- If the permissions cannot be granted at the resource level, All Resources is used in the Resource type column of the operation.
Condition Key: the condition key that is defined by the cloud service.
Associated operation: other operations that the RAM user or the RAM role must have permissions to perform to complete the operation. To complete the operation, the RAM user or the RAM role must have the permissions to perform the associated operations.

Operation	Access level	Resource type	Condition key	Associated operation
ess:DescribeScalingRules	get	All Resources ``	none	none

Request parameters

Parameter	Type	Required	Description	Example
RegionId	string	Yes	The region ID of the scaling group to which the scaling rules that you want to query belong.	cn-qingdao
PageNumber	integer	No	The page number. Pages start from page 1. Default value: 1.	1
PageSize	integer	No	The number of entries per page. Maximum value: 50. Default value: 10.	50
ScalingGroupId	string	No	The ID of the scaling group.	asg-bp1ffogfdauy0jw0****
ScalingRuleType	string	No	The type of the scaling rule. Valid values: SimpleScalingRule: adjusts the number of ECS instances based on the values of the AdjustmentType and AdjustmentValue parameters. TargetTrackingScalingRule: calculates the number of ECS instances that need to be scaled in a dynamic manner and maintains the value of a predefined metric close to the value of the TargetValue parameter. StepScalingRule: scales ECS instances in steps based on the specified thresholds and metric values. PredictiveScalingRule: uses machine learning to analyze historical monitoring data of the scaling group and predicts the future values of metrics. In addition, Auto Scaling automatically creates scheduled tasks to adjust the boundary values for the scaling group.	SimpleScalingRule
ShowAlarmRules	boolean	No	Specifies whether to return the event-triggered tasks that are associated with the scaling rule. Valid values: true false Default value: false.	false
ScalingRuleIds	array	No	The IDs of the scaling rules that you want to query.
	string	No	The IDs of the scaling rules that you want to query.	asr-bp1dvirgwkoowxk7****
ScalingRuleNames	array	No	The names of the scaling rules that you want to query.
	string	No	The names of the scaling rules that you want to query.	scalingrule****
ScalingRuleAris	array	No	The unique identifiers of the scaling rules that you want to query.
	string	No	The unique identifiers of the scaling rules that you want to query.	ari:acs:ess:cn-hangzhou:140692647406**:scalingrule/asr-bp1dvirgwkoowxk7**

Response parameters

Parameter	Type	Description	Example
	object
RequestId	string	The ID of the request.	473469C7-AA6F-4DC5-B3DB-A3DC0DE3****
PageNumber	integer	The page number of the returned page.	1
PageSize	integer	The number of entries returned per page.	50
TotalCount	integer	The total number of scaling rules.	1
ScalingRules	array<object>	The scaling rules.
ScalingRule	object	The scaling rule.
MetricName	string	The name of the metric of the event-triggered task that is associated with the scaling rule.	CpuUtilization
AdjustmentType	string	The adjustment method of the scaling rule. Valid values: QuantityChangeInCapacity: adds or removes the specified number of Elastic Compute Service (ECS) instances to or from the scaling group. PercentChangeInCapacity: adds or removes the specified percentage of ECS instances to or from the scaling group. TotalCapacity: adjusts the number of ECS instances in the scaling group to the specified number.	QuantityChangeInCapacity
InitialMaxSize	integer	The maximum number of ECS instances that can be contained in the scaling group. If you specify this parameter, you must also specify PredictiveValueBehavior.	100
EstimatedInstanceWarmup	integer	The warm-up period of instances. During the warm-up period, a series of preparation measures are taken for the new instances. Performance metrics of instances being warmed up are not counted towards the monitoring range.	300
ScaleOutEvaluationCount	integer	The number of consecutive times that the event-triggered task created for scale-out purposes must meet the threshold conditions before an alert is triggered. After a target tracking scaling rule is created, an event-triggered task is automatically created and associated with the target tracking scaling rule.	3
PredictiveScalingMode	string	The mode of the predictive scaling rule. Valid values: PredictAndScale: provides predictions and creates prediction tasks. PredictOnly: provides predictions but does not create prediction tasks.	PredictAndScale
MinAdjustmentMagnitude	integer	The minimum number of instances that must be scaled. This parameter takes effect only if you set ScalingRuleType to SimpleScalingRule or StepScalingRule and set AdjustmentType to PercentChangeInCapacity.	1
ScalingRuleAri	string	The unique identifier of the scaling rule.	ari:acs:ess:cn-hangzhou:140692647406**:scalingrule/asr-bp1dvirgwkoowxk7**
PredictiveTaskBufferTime	integer	The amount of buffer time before prediction tasks are executed. By default, all prediction tasks that are automatically created based on a predictive scaling rule are executed on the hour. You can specify a buffer time for resource preparation before prediction tasks are executed. Valid values: 0 to 60. Unit: minutes.	30
MinSize	integer	The minimum number of ECS instances that must be contained in the scaling group.	1
ScalingGroupId	string	The ID of the scaling group.	asg-bp1ffogfdauy0jw0****
PredictiveValueBehavior	string	The action on the predicted maximum value. Valid values: MaxOverridePredictiveValue: uses the initial maximum capacity as the maximum value for prediction tasks if the predicted value is greater than the initial maximum capacity. PredictiveValueOverrideMax: uses the predicted value as the maximum value for prediction tasks when the predicted value is greater than the initial maximum capacity. PredictiveValueOverrideMaxWithBuffer: increases the predicted value by a ratio that is specified by PredictiveValueBuffer, and uses the increased value as the maximum value for prediction tasks if the predicted value increased by this ratio is greater than the initial maximum capacity.	MaxOverridePredictiveValue
TargetValue	float	The target value of the metric. If you set ScalingRuleType to TargetTrackingScalingRule or PredictiveScalingRule, Auto Scaling keeps the metric value close to the target value by adding instances to or removing instances from the scaling group.	0.125
Cooldown	integer	The cooldown period of the scaling rule. This parameter is available only if you set ScalingRuleType to SimpleScalingRule. Valid values: 0 to 86400. Unit: seconds.	20
MaxSize	integer	The maximum number of ECS instances that can be contained in the scaling group.	2
PredictiveValueBuffer	integer	The ratio based on which the predicted value is increased when PredictiveValueBehavior is set to PredictiveValueOverrideMaxWithBuffer. If the predicted value increased by this ratio is greater than the initial maximum capacity, the increased value is used as the maximum value for prediction tasks. Valid values: 0 to 100.	50
ScalingRuleType	string	The type of the scaling rule. Valid values: SimpleScalingRule: a simple scaling rule. Once a simple scaling rule is executed, Auto Scaling adjusts the number of ECS instances in the scaling group based on the values of AdjustmentType and AdjustmentValue. TargetTrackingScalingRule: a target tracking scaling rule. Once a target tracking scaling rule is executed, Auto Scaling dynamically calculates the number of ECS instances or elastic container instances to scale based on the predefined metric (MetricName) and attempts to maintain the metric value close to the specified target value (TargetValue). StepScalingRule: a step scaling rule. Once a step scaling rule is executed, Auto Scaling scales instances step by step based on the predefined thresholds and metric values. PredictiveScalingRule: a predictive scaling rule. Once a predictive scaling rule is executed, Auto Scaling analyzes the historical monitoring data based on the machine learning technology and predicts the trends of metric data. Auto Scaling also creates scheduled tasks to enable dynamic adjustment of the boundary values for the scaling group.	SimpleScalingRule
AdjustmentValue	integer	The number of instances that must be scaled based on the scaling rule.	1
ScaleInEvaluationCount	integer	The number of consecutive times that the event-triggered task for scale-in purposes must meet the threshold conditions before an alert is triggered. After a target tracking scaling rule is created, an event-triggered task is automatically created and associated with the target tracking scaling rule.	15
DisableScaleIn	boolean	Indicates whether scale-in is disabled. This parameter takes effect only if you set ScalingRuleType to TargetTrackingScalingRule. Valid values: true false	true
ScalingRuleName	string	The name of the scaling rule.	scalingrule****
ScalingRuleId	string	The ID of the scaling rule.	asr-bp1dvirgwkoowxk7****
Alarms	array<object>	The event-triggered tasks that are associated with the scaling rule. The value of this parameter is returned only if you set ShowAlarmRules to true. Otherwise, null is returned.
Alarm	object	The event-triggered tasks that are associated with the scaling rule. Event-triggered tasks that are associated with the scaling rule are returned only if you set the ShowAlarmRules parameter to true. Otherwise, an empty list is returned.
AlarmTaskId	string	The ID of the event-triggered task that is associated with the scaling rule.	asg-bp18p2yfxow2dloq**_1f9458d1-70e1-4bee-8c7f-7a47695b**
ComparisonOperator	string	The comparison operator between the statistical value and the threshold of the metric of the event-triggered task that is associated with the scaling rule. The comparison operator indicates the relationship in which the metric value and the metric threshold can meet the alert condition. Valid value if the metric value is greater than or equal to the threshold: >= Valid value if the metric value is less than or equal to the threshold: <= Valid value if the metric value is greater than the threshold: > Valid value if the metric value is less than the threshold: <	>=
MetricName	string	The name of the metric of the event-triggered task that is associated with the scaling rule.	CpuUtilization
EvaluationCount	integer	The number of consecutive times when the event-triggered task that is associated with the scaling rule must meet the alert condition before an alert is triggered.	3
AlarmTaskName	string	The name of the event-triggered task that is associated with the scaling rule.	alarmtask****
MetricType	string	The type of the metric of the event-triggered task that is associated with the scaling rule. Valid values: system: system metrics custom: custom metrics	system
Threshold	float	The alert threshold of the event-triggered task that is associated with the scaling rule.	50
Statistics	string	The statistical method of the event-triggered task that is associated with the scaling rule. Valid values: Average Maximum Minimum	Average
Dimensions	array<object>	The dimensions of the event-triggered task that is associated with the scaling rule.
Dimension	object	The dimensions of the event-triggered task that is associated with the scaling rule.
DimensionKey	string	The key of the dimension that is associated with the metric. Valid values: ScalingGroupId: the ID of the scaling group. userId: the ID of the user account.	scaling_group
DimensionValue	string	The value of the dimension that is associated with the metric.	asg-bp18p2yfxow2dloq****
StepAdjustments	array<object>	The step adjustments of the step scaling rule.
StepAdjustment	object	The step adjustments of the step scaling rule.
MetricIntervalUpperBound	float	The upper limit of a step adjustment. Valid values: -9.999999E18 to 9.999999E18.	5.0
ScalingAdjustment	integer	The number of ECS instances that are scaled in a step adjustment.	1
MetricIntervalLowerBound	float	The lower limit of a step adjustment. Valid values: -9.999999E18 to 9.999999E18.	1.0
AlarmDimensions	array<object>	The dimensions. This parameter is applicable to target tracking scaling rules. You can specify this parameter if your predefined metric requires extra dimensions. For example, if you predefine the LoadBalancerRealServerAverageQps metric, you must use this parameter to specify the rulePool dimension.
AlarmDimension	object
DimensionKey	string	The dimension key of the metric.	rulePool
DimensionValue	string	The dimension value of the metric.	sgp-l1cbirz451yxu2dxxx

Examples

Sample success responses

JSONformat

{
  "RequestId": "473469C7-AA6F-4DC5-B3DB-A3DC0DE3****",
  "PageNumber": 1,
  "PageSize": 50,
  "TotalCount": 1,
  "ScalingRules": [
    {
      "MetricName": "CpuUtilization",
      "AdjustmentType": "QuantityChangeInCapacity",
      "InitialMaxSize": 100,
      "EstimatedInstanceWarmup": 300,
      "ScaleOutEvaluationCount": 3,
      "PredictiveScalingMode": "PredictAndScale",
      "MinAdjustmentMagnitude": 1,
      "ScalingRuleAri": "ari:acs:ess:cn-hangzhou:140692647406****:scalingrule/asr-bp1dvirgwkoowxk7****",
      "PredictiveTaskBufferTime": 30,
      "MinSize": 1,
      "ScalingGroupId": "asg-bp1ffogfdauy0jw0****",
      "PredictiveValueBehavior": "MaxOverridePredictiveValue",
      "TargetValue": 0.125,
      "Cooldown": 20,
      "MaxSize": 2,
      "PredictiveValueBuffer": 50,
      "ScalingRuleType": "SimpleScalingRule",
      "AdjustmentValue": 1,
      "ScaleInEvaluationCount": 15,
      "DisableScaleIn": true,
      "ScalingRuleName": "scalingrule****",
      "ScalingRuleId": "asr-bp1dvirgwkoowxk7****",
      "Alarms": [
        {
          "AlarmTaskId": "asg-bp18p2yfxow2dloq****_1f9458d1-70e1-4bee-8c7f-7a47695b****",
          "ComparisonOperator": ">=",
          "MetricName": "CpuUtilization",
          "EvaluationCount": 3,
          "AlarmTaskName": "alarmtask****",
          "MetricType": "system",
          "Threshold": 50,
          "Statistics": "Average",
          "Dimensions": [
            {
              "DimensionKey": "scaling_group",
              "DimensionValue": "asg-bp18p2yfxow2dloq****"
            }
          ]
        }
      ],
      "StepAdjustments": [
        {
          "MetricIntervalUpperBound": 5,
          "ScalingAdjustment": 1,
          "MetricIntervalLowerBound": 1
        }
      ],
      "AlarmDimensions": [
        {
          "DimensionKey": "rulePool",
          "DimensionValue": "sgp-l1cbirz451yxu2dxxx"
        }
      ],
      "MetricType": "",
      "HybridMonitorNamespace": "",
      "HybridMetrics": [
        {
          "Id": "",
          "Expression": "",
          "MetricName": "",
          "Statistic": "",
          "Dimensions": [
            {
              "DimensionKey": "",
              "DimensionValue": ""
            }
          ]
        }
      ]
    }
  ]
}

Error codes

For a list of error codes, visit the Service error codes.

Change history

Change time	Summary of changes	Operation
2024-09-13	The response structure of the API has changed	View Change Details
2023-04-03	The response structure of the API has changed	View Change Details