CreateScalingRule - Auto Scaling

Creates a scaling rule. The purpose of a scaling rule varies based on its type. You can use a scaling rule to trigger a scaling activity or adjust the boundary values for a scaling group. You can call the CreateScalingRule operation to create different types of scaling rules based on your business requirements. For example, if your business requires only automatic adjustment of boundary values for a scaling group, you can call the CreateScalingRule operation to create a predictive scaling rule.

Usage notes

Before you call the CreateScalingRule operation, take note of the following items:

If you set AdjustmentType to TotalCapacity, the total number of Elastic Compute Service (ECS) instances or elastic container instances in the scaling group is adjusted to a specific number when the scaling rule that you created by calling the CreateScalingRule operation is applied. You must set AdjustmentValue to an integer that is greater than 0.
If you set AdjustmentType to QuantityChangeInCapacity or PercentChangeInCapacity, a positive value of AdjustmentValue specifies that a specific number of ECS instances or elastic container instances are added to the scaling group. A negative value of AdjustmentValue specifies that a specific number of ECS instances or elastic container instances are removed from the scaling group.
If you set AdjustmentType to PercentChangeInCapacity, Auto Scaling calculates the number of ECS instances or elastic container instances to add or remove by using the following formula: Current capacity of the scaling group (Total Capacity) × Value of AdjustmentValue/100. The result is rounded off to determine the final adjustment count.
If you specify a cooldown period (Cooldown) for a scaling rule, the cooldown period of the scaling rule takes effect after you apply the scaling rule. If you do not specify a cooldown period (Cooldown) for a scaling rule, the default cooldown period (DefaultCooldown) of the scaling group takes effect after you apply the scaling rule.
You can create only a limited number of scaling rules for a scaling group. For more information, see Limits.
The following API operations may use the unique identifier of a scaling rule (ScalingRuleAri) that is returned by the CreateScalingRule operation:
- ExecuteScalingRule: You can call this operation to manually execute a scaling rule. When you call the ExecuteScalingRule operation, you can set ScalingRuleAri to the unique identifier of the scaling rule that you want to apply.
- CreateScheduledTask: You can call this operation to create a scheduled task for a scaling rule. When you call the CreateScheduledTask operation, you can set ScalingRuleAri to the unique identifier of the scaling rule for which you want to create a scheduled task.

Debugging

OpenAPI Explorer automatically calculates the signature value. For your convenience, we recommend that you call this operation in OpenAPI Explorer. OpenAPI Explorer dynamically generates the sample code of the operation for different SDKs.

Request parameters

Parameter	Type	Required	Example	Description
Action	String	Yes	CreateScalingRule	The operation that you want to perform. Set the value to CreateScalingRule.
ScalingGroupId	String	Yes	asg-bp1ffogfdauy0jw0****	The ID of the scaling group for which you want to create the scaling rule.
ScalingRuleName	String	No	scalingrule****	The name of the scaling rule. The name must be 2 to 64 characters in length, and can contain letters, digits, underscores (_), hyphens (-), and periods (.). The name must start with a letter or a digit. The name of each scaling rule must be unique within the same Alibaba Cloud account in a region. Note If you leave this parameter empty, the scaling rule ID is used.
Cooldown	Integer	No	60	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. You can leave this parameter empty.
MinAdjustmentMagnitude	Integer	No	1	The lower limit for the number of instances in each adjustment. This parameter takes effect only if you set `ScalingRuleType` to `SimpleScalingRule` or `StepScalingRule`, and `AdjustmentType` to PercentChangeInCapacity.
AdjustmentType	String	No	QuantityChangeInCapacity	The adjustment method used by the scaling rule. If you set ScalingRuleType to SimpleScalingRule or StepScalingRule, you must specify this parameter. Valid values: QuantityChangeInCapacity: adds a specific number of ECS instances to or removes a specific number of ECS instances from the scaling group. PercentChangeInCapacity: adds a specific percentage of ECS instances to or removes a specific percentage of ECS instances from the scaling group. TotalCapacity: adjusts the number of ECS instances in the scaling group to a specific number.
AdjustmentValue	Integer	No	100	The number of instances that can be added to or removed from the scaling group based on the scaling rule. If you set ScalingRuleType to SimpleScalingRule or StepScalingRule, you must specify this parameter. The maximum number of ECS instances that can be added or removed in a single scaling operation is 1,000 regardless of the scenario. The value range of this parameter varies based on the value of AdjustmentType. Valid values if you set AdjustmentType to QuantityChangeInCapacity: -1000 to 1000. Valid values if you set AdjustmentType to PercentChangeInCapacity: -100 to 10000. Valid values if you set AdjustmentType to TotalCapacity: 0 to 2000.
ScalingRuleType	String	No	SimpleScalingRule	The type of the scaling rule. Valid values: SimpleScalingRule: a simple scaling rule. After you apply a simple scaling rule, Auto Scaling adjusts the number of ECS instances or elastic container instances in the scaling group based on the values of AdjustmentType and AdjustmentValue. TargetTrackingScalingRule: a target tracking scaling rule. After you apply a target tracking scaling rule, Auto Scaling dynamically calculates the number of ECS instances or elastic container instances to scale based on a predefined metric (MetricName) and attempts to maintain the metric value close to the expected value (TargetValue). StepScalingRule: a step scaling rule. After you apply a step scaling rule, Auto Scaling scales instances step by step based on predefined thresholds and metric values. PredictiveScalingRule: uses machine learning to analyze the historical monitoring data of the scaling group and predicts the future values of metrics. In addition, Auto Scaling automatically creates scheduled tasks to specify the value range for the scaling group. Default value: SimpleScalingRule.
EstimatedInstanceWarmup	Integer	No	300	The warmup period of instances that can be added to or removed from the scaling group. You can specify this parameter only for simple scaling rules and step scaling rules. Auto Scaling adds ECS instances that are in the Warmup state to a scaling group, but does not report the monitoring data of the ECS instances to CloudMonitor during the warmup period. Note When Auto Scaling calculates the number of ECS instances that can be scaled, ECS instances in the Warmup state are not included in the current capacity of the scaling group. Valid values: 0 to 86400. Unit: seconds. Default value: 300.
MetricName	String	No	CpuUtilization	The predefined metric that you want to monitor. If you set ScalingRuleType to TargetTrackingScalingRule or PredictiveScalingRule, you must specify this parameter. Valid values if you set ScalingRuleType to TargetTrackingScalingRule: CpuUtilizationAgent (recommended): the CPU utilization. MemoryUtilization (recommended): the memory usage. CpuUtilization: the average CPU utilization. IntranetTx: the average outbound traffic over an internal network. IntranetRx: the average inbound traffic over an internal network. VpcInternetTx: the average outbound traffic from a virtual private cloud (VPC) to the Internet. VpcInternetRx: the average inbound traffic from the Internet to a VPC. LoadBalancerRealServerAverageQps: the queries per second (QPS) per Application Load Balancer (ALB) server group. Valid values if you set ScalingRuleType to PredictiveScalingRule: CpuUtilization: the average CPU utilization. IntranetRx: the average inbound traffic over an internal network. IntranetTx: the average outbound traffic over an internal network. For more information, see Event-triggered tasks of the system monitoring type.
TargetValue	Float	No	0.125	The expected value. If you set ScalingRuleType to TargetTrackingScalingRule or PredictiveScalingRule, you must specify this parameter. The value must be greater than 0 and can have up to three decimal places.
DisableScaleIn	Boolean	No	false	Specifies whether to disable scale-in. This parameter is available only if you set ScalingRuleType to TargetTrackingScalingRule. Default value: false.
ScaleInEvaluationCount	Integer	No	15	The number of consecutive times that the event-triggered task created for scale-in events must meet the threshold conditions before an alert is triggered. After you create a target tracking scaling rule, an event-triggered task is automatically created and associated with the scaling rule. Default value: 15.
ScaleOutEvaluationCount	Integer	No	3	The number of consecutive times that the event-triggered task created for scale-out events must meet the threshold conditions before an alert is triggered. After you create a target tracking scaling rule, an event-triggered task is automatically created and associated with the scaling rule. Default value: 3.
PredictiveScalingMode	String	No	PredictAndScale	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. Default value: PredictAndScale.
PredictiveValueBehavior	String	No	MaxOverridePredictiveValue	The action performed based 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 if 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 the ratio is greater than the initial maximum capacity. Default value: MaxOverridePredictiveValue.
PredictiveValueBuffer	Integer	No	50	The ratio based on which the predicted value is increased if you set `PredictiveValueBehavior` 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. Default value: 0.
PredictiveTaskBufferTime	Integer	No	30	The amount of buffer time before prediction tasks are run. By default, all prediction tasks that are automatically created based on a predictive scaling rule are run on the hour. You can specify a buffer time for resource preparation before prediction tasks are run. Valid values: 0 to 60. Unit: minutes. Default value: 0.
InitialMaxSize	Integer	No	100	The maximum number of ECS instances that can be added to the scaling group. If you specify InitialMaxSize, you must also specify PredictiveValueBehavior. The default value of this parameter is the value of MaxSize.
StepAdjustment.N.MetricIntervalUpperBound	Float	No	5.0	The upper limit of a step adjustment. This parameter takes effect only if you set ScalingRuleType to StepScalingRule. Valid values: -9.999999E18 to 9.999999E18.
StepAdjustment.N.ScalingAdjustment	Integer	No	1	The number of ECS instances that you want to scale in each step adjustment. This parameter is available only if you set ScalingRuleType to StepScalingRule.
StepAdjustment.N.MetricIntervalLowerBound	Float	No	1.0	The lower limit of a step adjustment. This parameter takes effect only if you set ScalingRuleType to StepScalingRule. Valid values: -9.999999E18 to 9.999999E18.
RegionId	String	No	cn-hangzhou	The region ID of the scaling group.
AlarmDimension.N.DimensionKey	String	No	rulePool	The dimension key of the metric.
AlarmDimension.N.DimensionValue	String	No	sgp-l1cbirz451yxu2****	The dimension value of the metric.

Response parameters

Parameter	Type	Example	Description
ScalingRuleAri	String	ari:acs:ess:cn-hangzhou:140692647406**:scalingrule/asr-bp1dvirgwkoowxk7**	The unique identifier of the scaling rule.
RequestId	String	473469C7-AA6F-4DC5-B3DB-A3DC0DE3****	The request ID.
ScalingRuleId	String	asr-bp1dvirgwkoowxk7****	The ID of the scaling rule. The ID is generated by the system and is globally unique.

Examples

Sample requests

http(s)://ess.aliyuncs.com/?Action=CreateScalingRule
&ScalingGroupId=asg-bp1ffogfdauy0jw0****
&ScalingRuleName=scalingrule****
&Cooldown=60
&MinAdjustmentMagnitude=1
&AdjustmentType=QuantityChangeInCapacity
&AdjustmentValue=100
&ScalingRuleType=SimpleScalingRule
&EstimatedInstanceWarmup=300
&MetricName=CpuUtilization
&TargetValue=0.125
&DisableScaleIn=false
&ScaleInEvaluationCount=15
&ScaleOutEvaluationCount=3
&PredictiveScalingMode=PredictAndScale
&PredictiveValueBehavior=MaxOverridePredictiveValue
&PredictiveValueBuffer=50
&PredictiveTaskBufferTime=30
&InitialMaxSize=100
&StepAdjustment=[{"MetricIntervalUpperBound":5.0,"ScalingAdjustment":1,"MetricIntervalLowerBound":1.0}]
&RegionId=cn-hangzhou
&AlarmDimension=[{"DimensionKey":"rulePool","DimensionValue":"sgp-l1cbirz451yxu2****"}]
&<Common request parameters>

Sample success responses

XML format

HTTP/1.1 200 OK
Content-Type:application/xml

<CreateScalingRuleResponse>
    <ScalingRuleAri>ari:acs:ess:cn-hangzhou:140692647406****:scalingrule/asr-bp1dvirgwkoowxk7****</ScalingRuleAri>
    <RequestId>473469C7-AA6F-4DC5-B3DB-A3DC0DE3****</RequestId>
    <ScalingRuleId>asr-bp1dvirgwkoowxk7****</ScalingRuleId>
</CreateScalingRuleResponse>

JSON format

HTTP/1.1 200 OK
Content-Type:application/json

{
  "ScalingRuleAri" : "ari:acs:ess:cn-hangzhou:140692647406****:scalingrule/asr-bp1dvirgwkoowxk7****",
  "RequestId" : "473469C7-AA6F-4DC5-B3DB-A3DC0DE3****",
  "ScalingRuleId" : "asr-bp1dvirgwkoowxk7****"
}

Error codes

For a list of error codes, see Service error codes.

HTTP status code	Error code	Error message	Description
404	InvalidScalingGroupId.NotFound	The specified scaling group does not exist.	The specified scaling group does not exist within your Alibaba Cloud account.
400	InvalidScalingRuleName.Duplicate	The specified value of parameter <parameter name> is duplicated.	The name of the scaling rule already exists.
400	QuotaExceeded.ScalingRule	Scaling rule quota exceeded in the specified scaling group.	The maximum number of scaling rules in the current scaling group has been reached.
400	TargetTrackingScalingRule.UnsupportedMetric	Specific metric is not supported for target tracking scaling rule.	The target tracking scaling rule does not support the specified metric.
400	TargetTrackingScalingRule.DumplicateMetric	Only one TargetTrackingScaling rule for a given metric specification is allowed.	The metric is already specified for another target tracking scaling rule in the scaling group.
400	InvalidMinAdjustmentMagnitudeMismatchAdjustmentType	MinAdjustmentMagnitude is not supported by the specified adjustment type.	MinAdjustmentMagnitude does not support the adjustment method of the scaling rule.
400	InvalidStepAdjustments.MultipleNullUpperBound	At most one StepAdjustment may have an unspecified upper bound.	A step adjustment that does not have an upper limit already exists.
400	InvalidStepAdjustments.MultipleNullLowerBound	At most one StepAdjustment may have an unspecified lower bound.	A step adjustment that does not have a lower limit already exists.
400	InvalidStepAdjustments.NoNullLowerBound	There must be a StepAdjustment with an unspecified lower bound when one StepAdjustment has a negative lower bound.	A step adjustment has a negative lower limit, but no step adjustment without a lower limit exists.
400	InvalidStepAdjustments.NoNullUpperBound	There must be a StepAdjustment with an unspecified upper bound when one StepAdjustment has a positive upper bound.	A step adjustment has a positive upper limit, but no step adjustment without an upper limit exists.
400	InvalidStepAdjustments.Gap	StepAdjustment intervals can not have gaps between them.	The step adjustments have gaps.
400	InvalidStepAdjustments.Overlap	StepAdjustment intervals can not overlap.	The ranges of step adjustments overlap.
400	InvalidStepAdjustments.LowerGtUpper	LowerBound must be less than the UpperBound for StepAdjustment :%s.	The lower limit of a step adjustment is greater than or equal to the upper limit.
400	InvalidStepAdjustments.BothNull	Both lower and upper bounds of a StepAdjustment can not be left unspecified.	You cannot specify an upper limit and a lower limit for a step adjustment at the same time.
400	InvalidStepAdjustments.MaxNum	Your scaling rule can have at most %s StepAdjustments.	The maximum number of step adjustments in a scaling group has been reached.
400	StepBeyondPermitRange	Specific parameter "%s" beyond permit range.	The specified upper limit or lower limit for a step adjustment is invalid.