Module Smaws_Client_AutoScaling.Types

Specifies whether instances in the Auto Scaling group can be returned to the warm pool on scale in.

The instance reuse policy.

The status of a warm pool that is marked for deletion.

The instance state to transition to after the lifecycle actions are complete.

The minimum number of instances to maintain in the warm pool.

The maximum number of instances that are allowed to be in the warm pool or in any state except Terminated for the Auto Scaling group.

The maximum number of vCPUs.

The minimum number of vCPUs.

The version number, $Latest, or $Default. To get the version number, use the Amazon EC2 DescribeLaunchTemplateVersions API operation. New launch template versions can be created using the Amazon EC2 CreateLaunchTemplateVersion API. If the value is $Latest, Amazon EC2 Auto Scaling selects the latest version of the launch template when launching instances. If the value is $Default, Amazon EC2 Auto Scaling selects the default version of the launch template when launching instances. The default value is $Default.

The name of the launch template. To get the template name, use the Amazon EC2 DescribeLaunchTemplates API operation. New launch templates can be created using the Amazon EC2 CreateLaunchTemplate API.

Conditional: You must specify either a LaunchTemplateId or a LaunchTemplateName.

The ID of the launch template. To get the template ID, use the Amazon EC2 DescribeLaunchTemplates API operation. New launch templates can be created using the Amazon EC2 CreateLaunchTemplate API.

Conditional: You must specify either a LaunchTemplateId or a LaunchTemplateName.

The memory maximum in MiB.

The memory minimum in MiB.

The memory maximum in GiB.

The memory minimum in GiB.

The maximum number of network interfaces.

The minimum number of network interfaces.

The storage maximum in GB.

The storage minimum in GB.

The maximum value in Mbps.

The minimum value in Mbps.

The maximum value.

The minimum value.

The memory maximum in MiB.

The memory minimum in MiB.

The maximum amount of network bandwidth, in gigabits per second (Gbps).

The minimum amount of network bandwidth, in gigabits per second (Gbps).

The instance family to use as a baseline reference.

Make sure that you specify the correct value for the instance family. The instance family is everything before the period (.) in the instance type name. For example, in the instance c6i.large, the instance family is c6i, not c6. For more information, see Amazon EC2 instance type naming conventions in Amazon EC2 Instance Types.

The following instance types are not supported for performance protection.

• c1
• g3| g3s
• hpc7g
• m1| m2
• mac1 | mac2 | mac2-m1ultra | mac2-m2 | mac2-m2pro
• p3dn | p4d | p5
• t1
• u-12tb1 | u-18tb1 | u-24tb1 | u-3tb1 | u-6tb1 | u-9tb1 | u7i-12tb | u7in-16tb | u7in-24tb | u7in-32tb

If you performance protection by specifying a supported instance family, the returned instance types will exclude the preceding unsupported instance families.

If you specify an unsupported instance family as a value for baseline performance, the API returns an empty response.

Specify an instance family to use as the baseline reference for CPU performance. All instance types that match your specified attributes will be compared against the CPU performance of the referenced instance family, regardless of CPU manufacturer or architecture differences.

Currently only one instance family can be specified in the list.

The CPU performance to consider, using an instance family as the baseline reference.

The baseline performance factors for the instance requirements.

The instance types to apply your specified attributes against. All other instance types are ignored, even if they match your specified attributes.

You can use strings with one or more wild cards, represented by an asterisk (*), to allow an instance type, size, or generation. The following are examples: m5.8xlarge, c5*.*, m5a.*, r*, *3*.

For example, if you specify c5*, Amazon EC2 Auto Scaling will allow the entire C5 instance family, which includes all C5a and C5n instance types. If you specify m5a.*, Amazon EC2 Auto Scaling will allow all the M5a instance types, but not the M5n instance types.

If you specify AllowedInstanceTypes, you can't specify ExcludedInstanceTypes.

Default: All instance types

The minimum and maximum amount of network bandwidth, in gigabits per second (Gbps).

Default: No minimum or maximum limits

The minimum and maximum total memory size for the accelerators on an instance type, in MiB.

Default: No minimum or maximum limits

Lists the accelerators that must be on an instance type.

• For instance types with NVIDIA A100 GPUs, specify a100.
• For instance types with NVIDIA V100 GPUs, specify v100.
• For instance types with NVIDIA K80 GPUs, specify k80.
• For instance types with NVIDIA T4 GPUs, specify t4.
• For instance types with NVIDIA M60 GPUs, specify m60.
• For instance types with AMD Radeon Pro V520 GPUs, specify radeon-pro-v520.
• For instance types with Xilinx VU9P FPGAs, specify vu9p.

Default: Any accelerator

Indicates whether instance types must have accelerators by specific manufacturers.

• For instance types with NVIDIA devices, specify nvidia.
• For instance types with AMD devices, specify amd.
• For instance types with Amazon Web Services devices, specify amazon-web-services.
• For instance types with Xilinx devices, specify xilinx.

Default: Any manufacturer

The minimum and maximum number of accelerators (GPUs, FPGAs, or Amazon Web Services Inferentia chips) for an instance type.

To exclude accelerator-enabled instance types, set Max to 0.

Default: No minimum or maximum limits

Lists the accelerator types that must be on an instance type.

• For instance types with GPU accelerators, specify gpu.
• For instance types with FPGA accelerators, specify fpga.
• For instance types with inference accelerators, specify inference.

Default: Any accelerator type

The minimum and maximum baseline bandwidth performance for an instance type, in Mbps. For more information, see Amazon EBS–optimized instances in the Amazon EC2 User Guide.

Default: No minimum or maximum limits

The minimum and maximum total local storage size for an instance type, in GB.

Default: No minimum or maximum limits

Indicates the type of local storage that is required.

• For instance types with hard disk drive (HDD) storage, specify hdd.
• For instance types with solid state drive (SSD) storage, specify ssd.

Default: Any local storage type

Indicates whether instance types with instance store volumes are included, excluded, or required. For more information, see Amazon EC2 instance store in the Amazon EC2 User Guide.

Default: included

The minimum and maximum number of network interfaces for an instance type.

Default: No minimum or maximum limits

Indicates whether instance types must provide On-Demand Instance hibernation support.

Default: false

Indicates whether burstable performance instance types are included, excluded, or required. For more information, see Burstable performance instances in the Amazon EC2 User Guide.

Default: excluded

Indicates whether bare metal instance types are included, excluded, or required.

Default: excluded

[Price protection] The price protection threshold for On-Demand Instances, as a percentage higher than an identified On-Demand price. The identified On-Demand price is the price of the lowest priced current generation C, M, or R instance type with your specified attributes. If no current generation C, M, or R instance type matches your attributes, then the identified price is from either the lowest priced current generation instance types or, failing that, the lowest priced previous generation instance types that match your attributes. When Amazon EC2 Auto Scaling selects instance types with your attributes, we will exclude instance types whose price exceeds your specified threshold.

The parameter accepts an integer, which Amazon EC2 Auto Scaling interprets as a percentage.

To turn off price protection, specify a high value, such as 999999.

If you set DesiredCapacityType to vcpu or memory-mib, the price protection threshold is applied based on the per-vCPU or per-memory price instead of the per instance price.

Default: 20

[Price protection] The price protection threshold for Spot Instances, as a percentage of an identified On-Demand price. The identified On-Demand price is the price of the lowest priced current generation C, M, or R instance type with your specified attributes. If no current generation C, M, or R instance type matches your attributes, then the identified price is from either the lowest priced current generation instance types or, failing that, the lowest priced previous generation instance types that match your attributes. When Amazon EC2 Auto Scaling selects instance types with your attributes, we will exclude instance types whose price exceeds your specified threshold.

The parameter accepts an integer, which Amazon EC2 Auto Scaling interprets as a percentage.

If you set DesiredCapacityType to vcpu or memory-mib, the price protection threshold is based on the per-vCPU or per-memory price instead of the per instance price.

Only one of SpotMaxPricePercentageOverLowestPrice or MaxSpotPriceAsPercentageOfOptimalOnDemandPrice can be specified. If you don't specify either, Amazon EC2 Auto Scaling will automatically apply optimal price protection to consistently select from a wide range of instance types. To indicate no price protection threshold for Spot Instances, meaning you want to consider all instance types that match your attributes, include one of these parameters and specify a high value, such as 999999.

[Price protection] The price protection threshold for Spot Instances, as a percentage higher than an identified Spot price. The identified Spot price is the price of the lowest priced current generation C, M, or R instance type with your specified attributes. If no current generation C, M, or R instance type matches your attributes, then the identified price is from either the lowest priced current generation instance types or, failing that, the lowest priced previous generation instance types that match your attributes. When Amazon EC2 Auto Scaling selects instance types with your attributes, we will exclude instance types whose price exceeds your specified threshold.

The parameter accepts an integer, which Amazon EC2 Auto Scaling interprets as a percentage.

If you set DesiredCapacityType to vcpu or memory-mib, the price protection threshold is based on the per-vCPU or per-memory price instead of the per instance price.

Only one of SpotMaxPricePercentageOverLowestPrice or MaxSpotPriceAsPercentageOfOptimalOnDemandPrice can be specified. If you don't specify either, Amazon EC2 Auto Scaling will automatically apply optimal price protection to consistently select from a wide range of instance types. To indicate no price protection threshold for Spot Instances, meaning you want to consider all instance types that match your attributes, include one of these parameters and specify a high value, such as 999999.

Indicates whether current or previous generation instance types are included.

• For current generation instance types, specify current. The current generation includes EC2 instance types currently recommended for use. This typically includes the latest two to three generations in each instance family. For more information, see Instance types in the Amazon EC2 User Guide.
• For previous generation instance types, specify previous.

Default: Any current or previous generation

The instance types to exclude. You can use strings with one or more wild cards, represented by an asterisk (*), to exclude an instance family, type, size, or generation. The following are examples: m5.8xlarge, c5*.*, m5a.*, r*, *3*.

For example, if you specify c5*, you are excluding the entire C5 instance family, which includes all C5a and C5n instance types. If you specify m5a.*, Amazon EC2 Auto Scaling will exclude all the M5a instance types, but not the M5n instance types.

If you specify ExcludedInstanceTypes, you can't specify AllowedInstanceTypes.

Default: No excluded instance types

The minimum and maximum amount of memory per vCPU for an instance type, in GiB.

Default: No minimum or maximum limits

Lists which specific CPU manufacturers to include.

• For instance types with Intel CPUs, specify intel.
• For instance types with AMD CPUs, specify amd.
• For instance types with Amazon Web Services CPUs, specify amazon-web-services.
• For instance types with Apple CPUs, specify apple.

Don't confuse the CPU hardware manufacturer with the CPU hardware architecture. Instances will be launched with a compatible CPU architecture based on the Amazon Machine Image (AMI) that you specify in your launch template.

Default: Any manufacturer

The minimum and maximum instance memory size for an instance type, in MiB.

The minimum and maximum number of vCPUs for an instance type.

The ID of the Amazon Machine Image (AMI) to use for instances launched with this override. When using Instance Refresh with ReplaceRootVolume strategy, this specifies the AMI for root volume replacement operations.

For ReplaceRootVolume operations:

• All overrides in the MixedInstancesPolicy must specify an ImageId
• The AMI must contain only a single root volume
• Root volume replacement doesn't support multi-volume AMIs

The instance requirements. Amazon EC2 Auto Scaling uses your specified requirements to identify instance types. Then, it uses your On-Demand and Spot allocation strategies to launch instances from these instance types.

You can specify up to four separate sets of instance requirements per Auto Scaling group. This is useful for provisioning instances from different Amazon Machine Images (AMIs) in the same Auto Scaling group. To do this, create the AMIs and create a new launch template for each AMI. Then, create a compatible set of instance requirements for each launch template.

If you specify InstanceRequirements, you can't specify InstanceType.

Provides a launch template for the specified instance type or set of instance requirements. For example, some instance types might require a launch template with a different AMI. If not provided, Amazon EC2 Auto Scaling uses the launch template that's specified in the LaunchTemplate definition. For more information, see Specifying a different launch template for an instance type in the Amazon EC2 Auto Scaling User Guide.

You can specify up to 20 launch templates per Auto Scaling group. The launch templates specified in the overrides and in the LaunchTemplate definition count towards this limit.

If you provide a list of instance types to use, you can specify the number of capacity units provided by each instance type in terms of virtual CPUs, memory, storage, throughput, or other relative performance characteristic. When a Spot or On-Demand Instance is launched, the capacity units count toward the desired capacity. Amazon EC2 Auto Scaling launches instances until the desired capacity is totally fulfilled, even if this results in an overage. For example, if there are two units remaining to fulfill capacity, and Amazon EC2 Auto Scaling can only launch an instance with a WeightedCapacity of five units, the instance is launched, and the desired capacity is exceeded by three units. For more information, see Configure an Auto Scaling group to use instance weights in the Amazon EC2 Auto Scaling User Guide. Value must be in the range of 1–999.

If you specify a value for WeightedCapacity for one instance type, you must specify a value for WeightedCapacity for all of them.

Every Auto Scaling group has three size parameters (DesiredCapacity, MaxSize, and MinSize). Usually, you set these sizes based on a specific number of instances. However, if you configure a mixed instances policy that defines weights for the instance types, you must specify these sizes with the same units that you use for weighting instances.

The instance type, such as m3.xlarge. You must specify an instance type that is supported in your requested Region and Availability Zones. For more information, see Instance types in the Amazon EC2 User Guide.

You can specify up to 40 instance types per Auto Scaling group.

Any properties that you specify override the same properties in the launch template.

The launch template.

The maximum price per unit hour that you are willing to pay for a Spot Instance. If your maximum price is lower than the Spot price for the instance types that you selected, your Spot Instances are not launched. We do not recommend specifying a maximum price because it can lead to increased interruptions. When Spot Instances launch, you pay the current Spot price. To remove a maximum price that you previously set, include the property but specify an empty string ("") for the value.

If you specify a maximum price, your instances will be interrupted more frequently than if you do not specify one.

Valid Range: Minimum value of 0.001

The number of Spot Instance pools across which to allocate your Spot Instances. The Spot pools are determined from the different instance types in the overrides. Valid only when the SpotAllocationStrategy is lowest-price. Value must be in the range of 1–20.

Default: 2

The allocation strategy to apply to your Spot Instances when they are launched. Possible instance types are determined by the launch template overrides that you specify.

The following lists the valid values:

capacity-optimized Requests Spot Instances using pools that are optimally chosen based on the available Spot capacity. This strategy has the lowest risk of interruption. To give certain instance types a higher chance of launching first, use capacity-optimized-prioritized.

capacity-optimized-prioritized You set the order of instance types for the launch template overrides from highest to lowest priority (from first to last in the list). Amazon EC2 Auto Scaling honors the instance type priorities on a best effort basis but optimizes for capacity first. Note that if the On-Demand allocation strategy is set to prioritized, the same priority is applied when fulfilling On-Demand capacity. This is not a valid value for Auto Scaling groups that specify InstanceRequirements.

lowest-price Requests Spot Instances using the lowest priced pools within an Availability Zone, across the number of Spot pools that you specify for the SpotInstancePools property. To ensure that your desired capacity is met, you might receive Spot Instances from several pools. This is the default value, but it might lead to high interruption rates because this strategy only considers instance price and not available capacity.

price-capacity-optimized (recommended) The price and capacity optimized allocation strategy looks at both price and capacity to select the Spot Instance pools that are the least likely to be interrupted and have the lowest possible price.

Controls the percentages of On-Demand Instances and Spot Instances for your additional capacity beyond OnDemandBaseCapacity. Expressed as a number (for example, 20 specifies 20% On-Demand Instances, 80% Spot Instances). If set to 100, only On-Demand Instances are used.

Default: 100

The minimum amount of the Auto Scaling group's capacity that must be fulfilled by On-Demand Instances. This base portion is launched first as your group scales.

This number has the same unit of measurement as the group's desired capacity. If you change the default unit of measurement (number of instances) by specifying weighted capacity values in your launch template overrides list, or by changing the default desired capacity type setting of the group, you must specify this number using the same unit of measurement.

Default: 0

The allocation strategy to apply to your On-Demand Instances when they are launched. Possible instance types are determined by the launch template overrides that you specify.

The following lists the valid values:

lowest-price Uses price to determine which instance types are the highest priority, launching the lowest priced instance types within an Availability Zone first. This is the default value for Auto Scaling groups that specify InstanceRequirements.

prioritized You set the order of instance types for the launch template overrides from highest to lowest priority (from first to last in the list). Amazon EC2 Auto Scaling launches your highest priority instance types first. If all your On-Demand capacity cannot be fulfilled using your highest priority instance type, then Amazon EC2 Auto Scaling launches the remaining capacity using the second priority instance type, and so on. This is the default value for Auto Scaling groups that don't specify InstanceRequirements and cannot be used for groups that do.

The instances distribution.

One or more launch templates and the instance types (overrides) that are used to launch EC2 instances to fulfill On-Demand and Spot capacities.

Specifies the upper threshold as a percentage of the desired capacity of the Auto Scaling group. It represents the maximum percentage of the group that can be in service and healthy, or pending, to support your workload when replacing instances. Value range is 100 to 200. To clear a previously set value, specify a value of -1.

Both MinHealthyPercentage and MaxHealthyPercentage must be specified, and the difference between them cannot be greater than 100. A large range increases the number of instances that can be replaced at the same time.

Specifies the lower threshold as a percentage of the desired capacity of the Auto Scaling group. It represents the minimum percentage of the group to keep in service, healthy, and ready to use to support your workload when replacing instances. Value range is 0 to 100. To clear a previously set value, specify a value of -1.

If launches fail in an Availability Zone, the following strategies are available. The default is balanced-best-effort.

• balanced-only - If launches fail in an Availability Zone, Auto Scaling will continue to attempt to launch in the unhealthy zone to preserve a balanced distribution.
• balanced-best-effort - If launches fail in an Availability Zone, Auto Scaling will attempt to launch in another healthy Availability Zone instead.
• reservations-then-balanced - Auto Scaling will first attempt to launch into your Capacity Reservations, and then balance any remaining capacity across the healthy Availability Zones.

Specifies the health check behavior for the impaired Availability Zone in an active zonal shift. If you select Replace unhealthy, instances that appear unhealthy will be replaced in all Availability Zones. If you select Ignore unhealthy, instances will not be replaced in the Availability Zone with the active zonal shift. For more information, see Auto Scaling group zonal shift in the Amazon EC2 Auto Scaling User Guide.

If true, enable zonal shift for your Auto Scaling group.

The resource group ARNs of the Capacity Reservation to launch instances into.

The Capacity Reservation IDs to launch instances into.

Describes a target Capacity Reservation or Capacity Reservation resource group.

The capacity reservation preference. The following options are available:

• capacity-reservations-only - Auto Scaling will only launch instances into a Capacity Reservation or Capacity Reservation resource group. If capacity isn't available, instances will fail to launch.
• capacity-reservations-first - Auto Scaling will try to launch instances into a Capacity Reservation or Capacity Reservation resource group first. If capacity isn't available, instances will run in On-Demand capacity.
• none - Auto Scaling will not launch instances into a Capacity Reservation. Instances will run in On-Demand capacity.
• default - Auto Scaling uses the Capacity Reservation preference from your launch template or an open Capacity Reservation.

Specifies the action when a termination lifecycle hook is abandoned due to failure, timeout, or explicit abandonment (calling CompleteLifecycleAction).

Set to retain to move instances to a retained state. Set to terminate for default termination behavior.

Retained instances don't count toward desired capacity and remain until you call TerminateInstanceInAutoScalingGroup.

Specifies the conditions that trigger instance retention behavior. These triggers determine when instances should move to a Retained state instead of automatic termination. This allows you to maintain control over instance management when lifecycles transition and operations fail.

The deletion protection setting for the Auto Scaling group. This setting helps safeguard your Auto Scaling group and its instances by controlling whether the DeleteAutoScalingGroup operation is allowed. When deletion protection is enabled, users cannot delete the Auto Scaling group according to the specified protection level until the setting is changed back to a less restrictive level.

The valid values are none, prevent-force-deletion, and prevent-all-deletion.

Default: none

For more information, see Configure deletion protection for your Amazon EC2 Auto Scaling resources in the Amazon EC2 Auto Scaling User Guide.

The instance lifecycle policy for the Auto Scaling group. This policy controls instance behavior when an instance transitions through its lifecycle states. Configure retention triggers to specify when instances should move to a Retained state instead of automatic termination.

For more information, see Control instance retention with instance lifecycle policies in the Amazon EC2 Auto Scaling User Guide.

The capacity reservation specification for the Auto Scaling group.

If you enable zonal shift with cross-zone disabled load balancers, capacity could become imbalanced across Availability Zones. To skip the validation, specify true. For more information, see Auto Scaling group zonal shift in the Amazon EC2 Auto Scaling User Guide.

The policy for Availability Zone impairment.

The instance capacity distribution across Availability Zones.

An instance maintenance policy. For more information, see Set instance maintenance policy in the Amazon EC2 Auto Scaling User Guide.

The amount of time, in seconds, until a new instance is considered to have finished initializing and resource consumption to become stable after it enters the InService state.

During an instance refresh, Amazon EC2 Auto Scaling waits for the warm-up period after it replaces an instance before it moves on to replacing the next instance. Amazon EC2 Auto Scaling also waits for the warm-up period before aggregating the metrics for new instances with existing instances in the Amazon CloudWatch metrics that are used for scaling, resulting in more reliable usage data. For more information, see Set the default instance warmup for an Auto Scaling group in the Amazon EC2 Auto Scaling User Guide.

To manage various warm-up settings at the group level, we recommend that you set the default instance warmup, even if it is set to 0 seconds. To remove a value that you previously set, include the property but specify -1 for the value. However, we strongly recommend keeping the default instance warmup enabled by specifying a value of 0 or other nominal value.

The unit of measurement for the value specified for desired capacity. Amazon EC2 Auto Scaling supports DesiredCapacityType for attribute-based instance type selection only. For more information, see Create a mixed instances group using attribute-based instance type selection in the Amazon EC2 Auto Scaling User Guide.

By default, Amazon EC2 Auto Scaling specifies units, which translates into number of instances.

Valid values: units | vcpu | memory-mib

Reserved.

Enables or disables Capacity Rebalancing. If Capacity Rebalancing is disabled, proactive replacement of at-risk Spot Instances does not occur. For more information, see Capacity Rebalancing in Auto Scaling to replace at-risk Spot Instances in the Amazon EC2 Auto Scaling User Guide.

To suspend rebalancing across Availability Zones, use the SuspendProcesses API.

The maximum amount of time, in seconds, that an instance can be in service. The default is null. If specified, the value must be either 0 or a number equal to or greater than 86,400 seconds (1 day). To clear a previously set value, specify a new value of 0. For more information, see Replacing Auto Scaling instances based on maximum instance lifetime in the Amazon EC2 Auto Scaling User Guide.

The Amazon Resource Name (ARN) of the service-linked role that the Auto Scaling group uses to call other Amazon Web Services on your behalf. For more information, see Service-linked roles in the Amazon EC2 Auto Scaling User Guide.

Indicates whether newly launched instances are protected from termination by Amazon EC2 Auto Scaling when scaling in. For more information about preventing instances from terminating on scale in, see Use instance scale-in protection in the Amazon EC2 Auto Scaling User Guide.

A policy or a list of policies that are used to select the instances to terminate. The policies are executed in the order that you list them. For more information, see Configure termination policies for Amazon EC2 Auto Scaling in the Amazon EC2 Auto Scaling User Guide.

Valid values: Default | AllocationStrategy | ClosestToNextInstanceHour | NewestInstance | OldestInstance | OldestLaunchConfiguration | OldestLaunchTemplate | arn:aws:lambda:region:account-id:function:my-function:my-alias

A comma-separated list of subnet IDs for a virtual private cloud (VPC). If you specify VPCZoneIdentifier with AvailabilityZones, the subnets that you specify must reside in those Availability Zones.

The name of an existing placement group into which to launch your instances. To remove the placement group setting, pass an empty string for placement-group. For more information about placement groups, see Placement groups in the Amazon EC2 User Guide.

A cluster placement group is a logical grouping of instances within a single Availability Zone. You cannot specify multiple Availability Zones and a cluster placement group.

The amount of time, in seconds, that Amazon EC2 Auto Scaling waits before checking the health status of an EC2 instance that has come into service and marking it unhealthy due to a failed health check. This is useful if your instances do not immediately pass their health checks after they enter the InService state. For more information, see Set the health check grace period for an Auto Scaling group in the Amazon EC2 Auto Scaling User Guide.

A comma-separated value string of one or more health check types.

The valid values are EC2, EBS, ELB, and VPC_LATTICE. EC2 is the default health check and cannot be disabled. For more information, see Health checks for instances in an Auto Scaling group in the Amazon EC2 Auto Scaling User Guide.

Only specify EC2 if you must clear a value that was previously set.

A list of Availability Zone IDs for the Auto Scaling group. You cannot specify both AvailabilityZones and AvailabilityZoneIds in the same request.

One or more Availability Zones for the group.

Only needed if you use simple scaling policies.

The amount of time, in seconds, between one scaling activity ending and another one starting due to simple scaling policies. For more information, see Scaling cooldowns for Amazon EC2 Auto Scaling in the Amazon EC2 Auto Scaling User Guide.

The desired capacity is the initial capacity of the Auto Scaling group after this operation completes and the capacity it attempts to maintain. This number must be greater than or equal to the minimum size of the group and less than or equal to the maximum size of the group.

The maximum size of the Auto Scaling group.

With a mixed instances policy that uses instance weighting, Amazon EC2 Auto Scaling may need to go above MaxSize to meet your capacity requirements. In this event, Amazon EC2 Auto Scaling will never go above MaxSize by more than your largest instance weight (weights that define how many units each instance contributes to the desired capacity of the group).

The minimum size of the Auto Scaling group.

The mixed instances policy. For more information, see Auto Scaling groups with multiple instance types and purchase options in the Amazon EC2 Auto Scaling User Guide.

The launch template and version to use to specify the updates. If you specify LaunchTemplate in your update request, you can't specify LaunchConfigurationName or MixedInstancesPolicy.

The name of the launch configuration. If you specify LaunchConfigurationName in your update request, you can't specify LaunchTemplate or MixedInstancesPolicy.

The name of the Auto Scaling group.

Provides additional context for the value of Identifier.

The following lists the valid values:

• elb if Identifier is the name of a Classic Load Balancer.
• elbv2 if Identifier is the ARN of an Application Load Balancer, Gateway Load Balancer, or Network Load Balancer target group.
• vpc-lattice if Identifier is the ARN of a VPC Lattice target group.

Required if the identifier is the name of a Classic Load Balancer.

Identifies the traffic source.

For Application Load Balancers, Gateway Load Balancers, Network Load Balancers, and VPC Lattice, this will be the Amazon Resource Name (ARN) for a target group in this account and Region. For Classic Load Balancers, this will be the name of the Classic Load Balancer in this account and Region.

For example:

• Application Load Balancer ARN: arn:aws:elasticloadbalancing:us-west-2:123456789012:targetgroup/my-targets/1234567890123456
• Classic Load Balancer name: my-classic-load-balancer
• VPC Lattice ARN: arn:aws:vpc-lattice:us-west-2:123456789012:targetgroup/tg-1234567890123456

To get the ARN of a target group for a Application Load Balancer, Gateway Load Balancer, or Network Load Balancer, or the name of a Classic Load Balancer, use the Elastic Load Balancing DescribeTargetGroups and DescribeLoadBalancers API operations.

To get the ARN of a target group for VPC Lattice, use the VPC Lattice GetTargetGroup API operation.

Provides additional context for the value of Identifier.

The following lists the valid values:

• elb if Identifier is the name of a Classic Load Balancer.
• elbv2 if Identifier is the ARN of an Application Load Balancer, Gateway Load Balancer, or Network Load Balancer target group.
• vpc-lattice if Identifier is the ARN of a VPC Lattice target group.

Required if the identifier is the name of a Classic Load Balancer.

The unique identifier of the traffic source.

Describes the current state of a traffic source.

The state values are as follows:

• Adding - The Auto Scaling instances are being registered with the load balancer or target group.
• Added - All Auto Scaling instances are registered with the load balancer or target group.
• InService - For an Elastic Load Balancing load balancer or target group, at least one Auto Scaling instance passed an ELB health check. For VPC Lattice, at least one Auto Scaling instance passed an VPC_LATTICE health check.
• Removing - The Auto Scaling instances are being deregistered from the load balancer or target group. If connection draining (deregistration delay) is enabled, Elastic Load Balancing or VPC Lattice waits for in-flight requests to complete before deregistering the instances.
• Removed - All Auto Scaling instances are deregistered from the load balancer or target group.

This is replaced by Identifier.

Indicates whether terminating the instance also decrements the size of the Auto Scaling group.

The ID of the instance.

The Amazon Resource Name (ARN) of the Auto Scaling group.

The state of the Auto Scaling group, which is either InService or Deleted.

The details about the activity.

A value between 0 and 100 that indicates the progress of the activity.

A friendly, more verbose description of the activity status.

The current status of the activity.

The end time of the activity.

The start time of the activity.

The reason the activity began.

A friendly, more verbose description of the activity.

The name of the Auto Scaling group.

The ID of the activity.

A scaling activity.

The value of the dimension.

The name of the dimension.

The dimensions for the metric. For the list of available dimensions, see the Amazon Web Services documentation available from the table in Amazon Web Services services that publish CloudWatch metrics in the Amazon CloudWatch User Guide.

Conditional: If you published your metric with dimensions, you must specify the same dimensions in your scaling policy.

The name of the metric.

The namespace of the metric. For more information, see the table in Amazon Web Services services that publish CloudWatch metrics in the Amazon CloudWatch User Guide.

The period of the metric in seconds. The default value is 60. Accepted values are 10, 30, and 60. For high resolution metric, set the value to less than 60. For more information, see Create a target tracking policy using high-resolution metrics for faster response.

The unit to use for the returned data points. For a complete list of the units that CloudWatch supports, see the MetricDatum data type in the Amazon CloudWatch API Reference.

The statistic to return. It can include any CloudWatch statistic or extended statistic. For a list of valid values, see the table in Statistics in the Amazon CloudWatch User Guide.

The most commonly used metric for scaling is Average.

The metric to use.

Indicates whether to return the timestamps and raw data values of this metric.

If you use any math expressions, specify true for this value for only the final math expression that the metric specification is based on. You must specify false for ReturnData for all the other metrics and expressions used in the metric specification.

If you are only retrieving metrics and not performing any math expressions, do not specify anything for ReturnData. This sets it to its default (true).

The period of the metric in seconds. The default value is 60. Accepted values are 10, 30, and 60. For high resolution metric, set the value to less than 60. For more information, see Create a target tracking policy using high-resolution metrics for faster response.

A human-readable label for this metric or expression. This is especially useful if this is a math expression, so that you know what the value represents.

Information about the metric data to return.

Conditional: Within each TargetTrackingMetricDataQuery object, you must specify either Expression or MetricStat, but not both.

The math expression to perform on the returned data, if this object is performing a math expression. This expression can use the Id of the other metrics to refer to those metrics, and can also use the Id of other expressions to use the result of those expressions.

Conditional: Within each TargetTrackingMetricDataQuery object, you must specify either Expression or MetricStat, but not both.

A short name that identifies the object's results in the response. This name must be unique among all TargetTrackingMetricDataQuery objects specified for a single scaling policy. If you are performing math expressions on this set of data, this name represents that data and can serve as a variable in the mathematical expression. The valid characters are letters, numbers, and underscores. The first character must be a lowercase letter.

A label that uniquely identifies a specific Application Load Balancer target group from which to determine the average request count served by your Auto Scaling group. You can't specify a resource label unless the target group is attached to the Auto Scaling group.

You create the resource label by appending the final portion of the load balancer ARN and the final portion of the target group ARN into a single value, separated by a forward slash (/). The format of the resource label is:

app/my-alb/778d41231b141a0f/targetgroup/my-alb-target-group/943f017f100becff.

Where:

• app// is the final portion of the load balancer ARN
• targetgroup// is the final portion of the target group ARN.

To find the ARN for an Application Load Balancer, use the DescribeLoadBalancers API operation. To find the ARN for the target group, use the DescribeTargetGroups API operation.

The metric type. The following predefined metrics are available:

• ASGAverageCPUUtilization - Average CPU utilization of the Auto Scaling group.
• ASGAverageNetworkIn - Average number of bytes received on all network interfaces by the Auto Scaling group.
• ASGAverageNetworkOut - Average number of bytes sent out on all network interfaces by the Auto Scaling group.
• ALBRequestCountPerTarget - Average Application Load Balancer request count per target for your Auto Scaling group.

The metrics to include in the target tracking scaling policy, as a metric data query. This can include both raw metric and metric math expressions.

The period of the metric in seconds. The default value is 60. Accepted values are 10, 30, and 60. For high resolution metric, set the value to less than 60. For more information, see Create a target tracking policy using high-resolution metrics for faster response.

The unit of the metric. For a complete list of the units that CloudWatch supports, see the MetricDatum data type in the Amazon CloudWatch API Reference.

The statistic of the metric.

The dimensions of the metric.

Conditional: If you published your metric with dimensions, you must specify the same dimensions in your scaling policy.

The namespace of the metric.

The name of the metric. To get the exact metric name, namespace, and dimensions, inspect the Metric object that is returned by a call to ListMetrics.

Indicates whether scaling in by the target tracking scaling policy is disabled. If scaling in is disabled, the target tracking scaling policy doesn't remove instances from the Auto Scaling group. Otherwise, the target tracking scaling policy can remove instances from the Auto Scaling group. The default is false.

The target value for the metric.

Some metrics are based on a count instead of a percentage, such as the request count for an Application Load Balancer or the number of messages in an SQS queue. If the scaling policy specifies one of these metrics, specify the target utilization as the optimal average request or message count per instance during any one-minute interval.

A customized metric. You must specify either a predefined metric or a customized metric.

A predefined metric. You must specify either a predefined metric or a customized metric.

Determines whether the tag is added to new instances as they are launched in the group.

The tag value.

The tag key.

The type of resource. The only supported value is auto-scaling-group.

The name of the group.

A string that indicates that the response contains more items than can be returned in a single response. To receive additional items, specify this string for the NextToken value when requesting the next set of items. This value is null when there are no more items to return.

One or more tags.

Determines whether the tag is added to new instances as they are launched in the group.

The tag value.

The tag key.

The type of resource. The only supported value is auto-scaling-group.

The name of the Auto Scaling group.

The reason that the process was suspended.

The name of the suspended process.

One or more of the following processes:

• Launch
• Terminate
• AddToLoadBalancer
• AlarmNotification
• AZRebalance
• HealthCheck
• InstanceRefresh
• ReplaceUnhealthy
• ScheduledActions

If you omit this property, all processes are specified.

The name of the Auto Scaling group.

The amount by which to scale, based on the specified adjustment type. A positive value adds to the current capacity while a negative number removes from the current capacity. For exact capacity, you must specify a non-negative value.

The upper bound for the difference between the alarm threshold and the CloudWatch metric. If the metric value is above the breach threshold, the upper bound is exclusive (the metric must be less than the threshold plus the upper bound). Otherwise, it is inclusive (the metric must be less than or equal to the threshold plus the upper bound). A null value indicates positive infinity.

The upper bound must be greater than the lower bound.

The lower bound for the difference between the alarm threshold and the CloudWatch metric. If the metric value is above the breach threshold, the lower bound is inclusive (the metric must be greater than or equal to the threshold plus the lower bound). Otherwise, it is exclusive (the metric must be greater than the threshold plus the lower bound). A null value indicates negative infinity.

Use this structure to launch multiple instance types and On-Demand Instances and Spot Instances within a single Auto Scaling group.

A mixed instances policy contains information that Amazon EC2 Auto Scaling can use to launch instances and help optimize your costs. For more information, see Auto Scaling groups with multiple instance types and purchase options in the Amazon EC2 Auto Scaling User Guide.

Describes the launch template and the version of the launch template that Amazon EC2 Auto Scaling uses to launch Amazon EC2 instances. For more information about launch templates, see Launch templates in the Amazon EC2 Auto Scaling User Guide.

The names of one or more CloudWatch alarms to monitor for the instance refresh. You can specify up to 10 alarms.

The amount of time, in seconds, to wait at the end of an instance refresh before the instance refresh is considered complete.

Specifies the maximum percentage of the group that can be in service and healthy, or pending, to support your workload when replacing instances. The value is expressed as a percentage of the desired capacity of the Auto Scaling group. Value range is 100 to 200.

If you specify MaxHealthyPercentage, you must also specify MinHealthyPercentage, and the difference between them cannot be greater than 100. A larger range increases the number of instances that can be replaced at the same time.

If you do not specify this property, the default is 100 percent, or the percentage set in the instance maintenance policy for the Auto Scaling group, if defined.

(Optional) The CloudWatch alarm specification. CloudWatch alarms can be used to identify any issues and fail the operation if an alarm threshold is met.

Choose the behavior that you want Amazon EC2 Auto Scaling to use if instances in Standby state are found.

The following lists the valid values:

Terminate Amazon EC2 Auto Scaling terminates instances that are in Standby.

Ignore Amazon EC2 Auto Scaling ignores instances that are in Standby and continues to replace instances that are in the InService state.

Wait (default) Amazon EC2 Auto Scaling waits one hour for you to return the instances to service. Otherwise, the instance refresh will fail.

Choose the behavior that you want Amazon EC2 Auto Scaling to use if instances protected from scale in are found.

The following lists the valid values:

Refresh Amazon EC2 Auto Scaling replaces instances that are protected from scale in.

Ignore Amazon EC2 Auto Scaling ignores instances that are protected from scale in and continues to replace instances that are not protected.

Wait (default) Amazon EC2 Auto Scaling waits one hour for you to remove scale-in protection. Otherwise, the instance refresh will fail.

(Optional) Indicates whether to roll back the Auto Scaling group to its previous configuration if the instance refresh fails or a CloudWatch alarm threshold is met. The default is false.

A rollback is not supported in the following situations:

• There is no desired configuration specified for the instance refresh.
• The Auto Scaling group has a launch template that uses an Amazon Web Services Systems Manager parameter instead of an AMI ID for the ImageId property.
• The Auto Scaling group uses the launch template's $Latest or $Default version.

For more information, see Undo changes with a rollback in the Amazon EC2 Auto Scaling User Guide.

(Optional) Indicates whether skip matching is enabled. If enabled (true), then Amazon EC2 Auto Scaling skips replacing instances that match the desired configuration. If no desired configuration is specified, then it skips replacing instances that have the same launch template and instance types that the Auto Scaling group was using before the start of the instance refresh. The default is false.

For more information, see Use an instance refresh with skip matching in the Amazon EC2 Auto Scaling User Guide.

(Optional) The amount of time, in seconds, to wait after a checkpoint before continuing. This property is optional, but if you specify a value for it, you must also specify a value for CheckpointPercentages. If you specify a value for CheckpointPercentages and not for CheckpointDelay, the CheckpointDelay defaults to 3600 (1 hour).

(Optional) Threshold values for each checkpoint in ascending order. Each number must be unique. To replace all instances in the Auto Scaling group, the last number in the array must be 100.

For usage examples, see Add checkpoints to an instance refresh in the Amazon EC2 Auto Scaling User Guide.

A time period, in seconds, during which an instance refresh waits before moving on to replacing the next instance after a new instance enters the InService state.

This property is not required for normal usage. Instead, use the DefaultInstanceWarmup property of the Auto Scaling group. The InstanceWarmup and DefaultInstanceWarmup properties work the same way. Only specify this property if you must override the DefaultInstanceWarmup property.

If you do not specify this property, the instance warmup by default is the value of the DefaultInstanceWarmup property, if defined (which is recommended in all cases), or the HealthCheckGracePeriod property otherwise.

Specifies the minimum percentage of the group to keep in service, healthy, and ready to use to support your workload to allow the operation to continue. The value is expressed as a percentage of the desired capacity of the Auto Scaling group. Value range is 0 to 100.

If you do not specify this property, the default is 90 percent, or the percentage set in the instance maintenance policy for the Auto Scaling group, if defined.

Sets your preferences for the instance refresh so that it performs as expected when you start it. Includes the instance warmup time, the minimum and maximum healthy percentages, and the behaviors that you want Amazon EC2 Auto Scaling to use if instances that are in Standby state or protected from scale in are found. You can also choose to enable additional features, such as the following:

• Auto rollback
• Checkpoints
• CloudWatch alarms
• Skip matching
• Bake time

The desired configuration. For example, the desired configuration can specify a new launch template or a new version of the current launch template.

Once the instance refresh succeeds, Amazon EC2 Auto Scaling updates the settings of the Auto Scaling group to reflect the new desired configuration.

When you specify a new launch template or a new version of the current launch template for your desired configuration, consider enabling the SkipMatching property in preferences. If it's enabled, Amazon EC2 Auto Scaling skips replacing instances that already use the specified launch template and instance types. This can help you reduce the number of replacements that are required to apply updates.

The strategy to use for the instance refresh. The default value is Rolling.

The name of the Auto Scaling group.

A unique ID for tracking the progress of the instance refresh.

Indicates whether the instance is protected from termination by Amazon EC2 Auto Scaling when scaling in.

The name of the Auto Scaling group.

One or more instance IDs. You can specify up to 50 instances.

If the Auto Scaling group of the specified instance has a HealthCheckGracePeriod specified for the group, by default, this call respects the grace period. Set this to False, to have the call not respect the grace period associated with the group.

For more information about the health check grace period, see Set the health check grace period for an Auto Scaling group in the Amazon EC2 Auto Scaling User Guide.

The health status of the instance. Set to Healthy to have the instance remain in service. Set to Unhealthy to have the instance be out of service. Amazon EC2 Auto Scaling terminates and replaces the unhealthy instance.

The ID of the instance.

Indicates whether Amazon EC2 Auto Scaling waits for the cooldown period to complete before initiating a scaling activity to set your Auto Scaling group to its new capacity. By default, Amazon EC2 Auto Scaling does not honor the cooldown period during manual scaling activities.

The desired capacity is the initial capacity of the Auto Scaling group after this operation completes and the capacity it attempts to maintain.

The name of the Auto Scaling group.

The time zone for the cron expression.

The desired capacity is the initial capacity of the Auto Scaling group after the scheduled action runs and the capacity it attempts to maintain.

The maximum size of the Auto Scaling group.

The minimum size of the Auto Scaling group.

The recurring schedule for the action, in Unix cron syntax format.

When StartTime and EndTime are specified with Recurrence, they form the boundaries of when the recurring action starts and stops.

The date and time in UTC for the recurring schedule to end. For example, "2019-06-01T00:00:00Z".

The date and time in UTC for this action to start. For example, "2019-06-01T00:00:00Z".

This property is no longer used.

The Amazon Resource Name (ARN) of the scheduled action.

The name of the scheduled action.

The name of the Auto Scaling group.

Specifies the time zone for a cron expression. If a time zone is not provided, UTC is used by default.

Valid values are the canonical names of the IANA time zones, derived from the IANA Time Zone Database (such as Etc/GMT+9 or Pacific/Tahiti). For more information, see https://en.wikipedia.org/wiki/List_of_tz_database_time_zones.

The desired capacity is the initial capacity of the Auto Scaling group after the scheduled action runs and the capacity it attempts to maintain.

The maximum size of the Auto Scaling group.

The minimum size of the Auto Scaling group.

The recurring schedule for the action, in Unix cron syntax format. This format consists of five fields separated by white spaces: [Minute] [Hour] [Day_of_Month] [Month_of_Year] [Day_of_Week]. The value must be in quotes (for example, "30 0 1 1,6,12 *"). For more information about this format, see Crontab.

When StartTime and EndTime are specified with Recurrence, they form the boundaries of when the recurring action starts and stops.

Cron expressions use Universal Coordinated Time (UTC) by default.

The date and time for the recurring schedule to end, in UTC.

The date and time for the action to start, in YYYY-MM-DDThh:mm:ssZ format in UTC/GMT only and in quotes (for example, "2019-06-01T00:00:00Z").

If you specify Recurrence and StartTime, Amazon EC2 Auto Scaling performs the action at this time, and then performs the action based on the specified recurrence.

If you try to schedule the action in the past, Amazon EC2 Auto Scaling returns an error message.

The name of the scaling action.

A string that indicates that the response contains more items than can be returned in a single response. To receive additional items, specify this string for the NextToken value when requesting the next set of items. This value is null when there are no more items to return.

The scheduled actions.

The Amazon Resource Name (ARN) of the alarm.

The name of the alarm.

A label that uniquely identifies a specific Application Load Balancer target group from which to determine the total and average request count served by your Auto Scaling group. You can't specify a resource label unless the target group is attached to the Auto Scaling group.

You create the resource label by appending the final portion of the load balancer ARN and the final portion of the target group ARN into a single value, separated by a forward slash (/). The format of the resource label is:

app/my-alb/778d41231b141a0f/targetgroup/my-alb-target-group/943f017f100becff.

Where:

• app// is the final portion of the load balancer ARN
• targetgroup// is the final portion of the target group ARN.

To find the ARN for an Application Load Balancer, use the DescribeLoadBalancers API operation. To find the ARN for the target group, use the DescribeTargetGroups API operation.

Indicates which metrics to use. There are two different types of metrics for each metric type: one is a load metric and one is a scaling metric. For example, if the metric type is ASGCPUUtilization, the Auto Scaling group's total CPU metric is used as the load metric, and the average CPU metric is used for the scaling metric.

A label that uniquely identifies a specific Application Load Balancer target group from which to determine the average request count served by your Auto Scaling group. You can't specify a resource label unless the target group is attached to the Auto Scaling group.

You create the resource label by appending the final portion of the load balancer ARN and the final portion of the target group ARN into a single value, separated by a forward slash (/). The format of the resource label is:

app/my-alb/778d41231b141a0f/targetgroup/my-alb-target-group/943f017f100becff.

Where:

• app// is the final portion of the load balancer ARN
• targetgroup// is the final portion of the target group ARN.

To find the ARN for an Application Load Balancer, use the DescribeLoadBalancers API operation. To find the ARN for the target group, use the DescribeTargetGroups API operation.

The metric type.

A label that uniquely identifies a specific Application Load Balancer target group from which to determine the request count served by your Auto Scaling group. You can't specify a resource label unless the target group is attached to the Auto Scaling group.

You create the resource label by appending the final portion of the load balancer ARN and the final portion of the target group ARN into a single value, separated by a forward slash (/). The format of the resource label is:

app/my-alb/778d41231b141a0f/targetgroup/my-alb-target-group/943f017f100becff.

Where:

• app// is the final portion of the load balancer ARN
• targetgroup// is the final portion of the target group ARN.

To find the ARN for an Application Load Balancer, use the DescribeLoadBalancers API operation. To find the ARN for the target group, use the DescribeTargetGroups API operation.

The metric type.

The unit to use for the returned data points. For a complete list of the units that CloudWatch supports, see the MetricDatum data type in the Amazon CloudWatch API Reference.

The statistic to return. It can include any CloudWatch statistic or extended statistic. For a list of valid values, see the table in Statistics in the Amazon CloudWatch User Guide.

The most commonly used metrics for predictive scaling are Average and Sum.

The CloudWatch metric to return, including the metric name, namespace, and dimensions. To get the exact metric name, namespace, and dimensions, inspect the Metric object that is returned by a call to ListMetrics.

Indicates whether to return the timestamps and raw data values of this metric.

If you use any math expressions, specify true for this value for only the final math expression that the metric specification is based on. You must specify false for ReturnData for all the other metrics and expressions used in the metric specification.

If you are only retrieving metrics and not performing any math expressions, do not specify anything for ReturnData. This sets it to its default (true).

A human-readable label for this metric or expression. This is especially useful if this is a math expression, so that you know what the value represents.

Information about the metric data to return.

Conditional: Within each MetricDataQuery object, you must specify either Expression or MetricStat, but not both.

The math expression to perform on the returned data, if this object is performing a math expression. This expression can use the Id of the other metrics to refer to those metrics, and can also use the Id of other expressions to use the result of those expressions.

Conditional: Within each MetricDataQuery object, you must specify either Expression or MetricStat, but not both.

A short name that identifies the object's results in the response. This name must be unique among all MetricDataQuery objects specified for a single scaling policy. If you are performing math expressions on this set of data, this name represents that data and can serve as a variable in the mathematical expression. The valid characters are letters, numbers, and underscores. The first character must be a lowercase letter.

One or more metric data queries to provide the data points for a scaling metric. Use multiple metric data queries only if you are performing a math expression on returned data.

One or more metric data queries to provide the data points for a load metric. Use multiple metric data queries only if you are performing a math expression on returned data.

One or more metric data queries to provide the data points for a capacity metric. Use multiple metric data queries only if you are performing a math expression on returned data.

The customized capacity metric specification.

The customized load metric specification.

The customized scaling metric specification.

The predefined load metric specification.

The predefined scaling metric specification.

The predefined metric pair specification from which Amazon EC2 Auto Scaling determines the appropriate scaling metric and load metric to use.

Specifies the target utilization.

Some metrics are based on a count instead of a percentage, such as the request count for an Application Load Balancer or the number of messages in an SQS queue. If the scaling policy specifies one of these metrics, specify the target utilization as the optimal average request or message count per instance during any one-minute interval.

The size of the capacity buffer to use when the forecast capacity is close to or exceeds the maximum capacity. The value is specified as a percentage relative to the forecast capacity. For example, if the buffer is 10, this means a 10 percent buffer, such that if the forecast capacity is 50, and the maximum capacity is 40, then the effective maximum capacity is 55.

If set to 0, Amazon EC2 Auto Scaling may scale capacity higher than the maximum capacity to equal but not exceed forecast capacity.

Required if the MaxCapacityBreachBehavior property is set to IncreaseMaxCapacity, and cannot be used otherwise.

Defines the behavior that should be applied if the forecast capacity approaches or exceeds the maximum capacity of the Auto Scaling group. Defaults to HonorMaxCapacity if not specified.

The following are possible values:

• HonorMaxCapacity - Amazon EC2 Auto Scaling can't increase the maximum capacity of the group when the forecast capacity is close to or exceeds the maximum capacity.
• IncreaseMaxCapacity - Amazon EC2 Auto Scaling can increase the maximum capacity of the group when the forecast capacity is close to or exceeds the maximum capacity. The upper limit is determined by the forecasted capacity and the value for MaxCapacityBuffer.

Use caution when allowing the maximum capacity to be automatically increased. This can lead to more instances being launched than intended if the increased maximum capacity is not monitored and managed. The increased maximum capacity then becomes the new normal maximum capacity for the Auto Scaling group until you manually update it. The maximum capacity does not automatically decrease back to the original maximum.

The amount of time, in seconds, by which the instance launch time can be advanced. For example, the forecast says to add capacity at 10:00 AM, and you choose to pre-launch instances by 5 minutes. In that case, the instances will be launched at 9:55 AM. The intention is to give resources time to be provisioned. It can take a few minutes to launch an EC2 instance. The actual amount of time required depends on several factors, such as the size of the instance and whether there are startup scripts to complete.

The value must be less than the forecast interval duration of 3600 seconds (60 minutes). Defaults to 300 seconds if not specified.

The predictive scaling mode. Defaults to ForecastOnly if not specified.

This structure includes the metrics and target utilization to use for predictive scaling.

This is an array, but we currently only support a single metric specification. That is, you can specify a target value and a single metric pair, or a target value and one scaling metric and one load metric.

A predictive scaling policy.

Indicates whether the policy is enabled (true) or disabled (false).

A target tracking scaling policy.

The CloudWatch alarms related to the policy.

The estimated time, in seconds, until a newly launched instance can contribute to the CloudWatch metrics.

The aggregation type for the CloudWatch metrics. The valid values are Minimum, Maximum, and Average.

A set of adjustments that enable you to scale based on the size of the alarm breach.

The duration of the policy's cooldown period, in seconds.

The amount by which to scale, based on the specified adjustment type. A positive value adds to the current capacity while a negative number removes from the current capacity.

The minimum value to scale by when the adjustment type is PercentChangeInCapacity.

Available for backward compatibility. Use MinAdjustmentMagnitude instead.

Specifies how the scaling adjustment is interpreted (for example, an absolute number or a percentage). The valid values are ChangeInCapacity, ExactCapacity, and PercentChangeInCapacity.

One of the following policy types:

• TargetTrackingScaling
• StepScaling
• SimpleScaling (default)
• PredictiveScaling

For more information, see Target tracking scaling policies and Step and simple scaling policies in the Amazon EC2 Auto Scaling User Guide.

The Amazon Resource Name (ARN) of the policy.

The name of the scaling policy.

The name of the Auto Scaling group.

The name of the Auto Scaling group.

The instance refresh ID associated with the request. This is the unique ID assigned to the instance refresh when it was started.

The number of instances remaining to update.

The percentage of instances in the Auto Scaling group that have been replaced. For each instance replacement, Amazon EC2 Auto Scaling tracks the instance's health status and warm-up time. When the instance's health status changes to healthy and the specified warm-up time passes, the instance is considered updated and is added to the percentage complete.

The number of instances remaining to update.

The percentage of instances in the warm pool that have been replaced. For each instance replacement, Amazon EC2 Auto Scaling tracks the instance's health status and warm-up time. When the instance's health status changes to healthy and the specified warm-up time passes, the instance is considered updated and is added to the percentage complete.

Reports progress on replacing instances that are in the warm pool.

Reports progress on replacing instances that are in the Auto Scaling group.

Reports progress on replacing instances in an Auto Scaling group that has a warm pool. This includes separate details for instances in the warm pool and instances in the Auto Scaling group (the live pool).

Indicates the value of InstancesToUpdate at the time the rollback started.

Indicates the value of PercentageComplete at the time the rollback started.

The date and time at which the rollback began.

The reason for this instance refresh rollback (for example, whether a manual or automatic rollback was initiated).

The ID of the instance.

A token that uniquely identifies a specific lifecycle action associated with an instance. Amazon EC2 Auto Scaling sends this token to the notification target that you specified when you created the lifecycle hook.

The name of the Auto Scaling group.

The name of the lifecycle hook.

Indicates whether instances in the Auto Scaling group can be returned to the warm pool on scale in. The default is to terminate instances in the Auto Scaling group when the group scales in.

Sets the instance state to transition to after the lifecycle actions are complete. Default is Stopped.

Specifies the minimum number of instances to maintain in the warm pool. This helps you to ensure that there is always a certain number of warmed instances available to handle traffic spikes. Defaults to 0 if not specified.

Specifies the maximum number of instances that are allowed to be in the warm pool or in any state except Terminated for the Auto Scaling group. This is an optional property. Specify it only if you do not want the warm pool size to be determined by the difference between the group's maximum capacity and its desired capacity.

If a value for MaxGroupPreparedCapacity is not specified, Amazon EC2 Auto Scaling launches and maintains the difference between the group's maximum capacity and its desired capacity. If you specify a value for MaxGroupPreparedCapacity, Amazon EC2 Auto Scaling uses the difference between the MaxGroupPreparedCapacity and the desired capacity instead.

The size of the warm pool is dynamic. Only when MaxGroupPreparedCapacity and MinSize are set to the same value does the warm pool have an absolute size.

If the desired capacity of the Auto Scaling group is higher than the MaxGroupPreparedCapacity, the capacity of the warm pool is 0, unless you specify a value for MinSize. To remove a value that you previously set, include the property but specify -1 for the value.

The name of the Auto Scaling group.

Specifies the time zone for a cron expression. If a time zone is not provided, UTC is used by default.

Valid values are the canonical names of the IANA time zones, derived from the IANA Time Zone Database (such as Etc/GMT+9 or Pacific/Tahiti). For more information, see https://en.wikipedia.org/wiki/List_of_tz_database_time_zones.

The desired capacity is the initial capacity of the Auto Scaling group after the scheduled action runs and the capacity it attempts to maintain. It can scale beyond this capacity if you add more scaling conditions.

You must specify at least one of the following properties: MaxSize, MinSize, or DesiredCapacity.

The maximum size of the Auto Scaling group.

The minimum size of the Auto Scaling group.

The recurring schedule for this action. This format consists of five fields separated by white spaces: [Minute] [Hour] [Day_of_Month] [Month_of_Year] [Day_of_Week]. The value must be in quotes (for example, "30 0 1 1,6,12 *"). For more information about this format, see Crontab.

When StartTime and EndTime are specified with Recurrence, they form the boundaries of when the recurring action starts and stops.

Cron expressions use Universal Coordinated Time (UTC) by default.

The date and time for the recurring schedule to end, in UTC. For example, "2021-06-01T00:00:00Z".

The date and time for this action to start, in YYYY-MM-DDThh:mm:ssZ format in UTC/GMT only and in quotes (for example, "2021-06-01T00:00:00Z").

If you specify Recurrence and StartTime, Amazon EC2 Auto Scaling performs the action at this time, and then performs the action based on the specified recurrence.

This property is no longer used.

The name of this scaling action.

The name of the Auto Scaling group.

A predictive scaling policy. Provides support for predefined and custom metrics.

Predefined metrics include CPU utilization, network in/out, and the Application Load Balancer request count.

For more information, see PredictiveScalingConfiguration in the Amazon EC2 Auto Scaling API Reference.

Required if the policy type is PredictiveScaling.

Indicates whether the scaling policy is enabled or disabled. The default is enabled. For more information, see Disable a scaling policy for an Auto Scaling group in the Amazon EC2 Auto Scaling User Guide.

A target tracking scaling policy. Provides support for predefined or custom metrics.

The following predefined metrics are available:

• ASGAverageCPUUtilization
• ASGAverageNetworkIn
• ASGAverageNetworkOut
• ALBRequestCountPerTarget

If you specify ALBRequestCountPerTarget for the metric, you must specify the ResourceLabel property with the PredefinedMetricSpecification.

For more information, see TargetTrackingConfiguration in the Amazon EC2 Auto Scaling API Reference.

Required if the policy type is TargetTrackingScaling.

Not needed if the default instance warmup is defined for the group.

The estimated time, in seconds, until a newly launched instance can contribute to the CloudWatch metrics. This warm-up period applies to instances launched due to a specific target tracking or step scaling policy. When a warm-up period is specified here, it overrides the default instance warmup.

Valid only if the policy type is TargetTrackingScaling or StepScaling.

The default is to use the value for the default instance warmup defined for the group. If default instance warmup is null, then EstimatedInstanceWarmup falls back to the value of default cooldown.

A set of adjustments that enable you to scale based on the size of the alarm breach.

Required if the policy type is StepScaling. (Not used with any other policy type.)

The aggregation type for the CloudWatch metrics. The valid values are Minimum, Maximum, and Average. If the aggregation type is null, the value is treated as Average.

Valid only if the policy type is StepScaling.

A cooldown period, in seconds, that applies to a specific simple scaling policy. When a cooldown period is specified here, it overrides the default cooldown.

Valid only if the policy type is SimpleScaling. For more information, see Scaling cooldowns for Amazon EC2 Auto Scaling in the Amazon EC2 Auto Scaling User Guide.

Default: None

The amount by which to scale, based on the specified adjustment type. A positive value adds to the current capacity while a negative number removes from the current capacity. For exact capacity, you must specify a non-negative value.

Required if the policy type is SimpleScaling. (Not used with any other policy type.)

The minimum value to scale by when the adjustment type is PercentChangeInCapacity. For example, suppose that you create a step scaling policy to scale out an Auto Scaling group by 25 percent and you specify a MinAdjustmentMagnitude of 2. If the group has 4 instances and the scaling policy is performed, 25 percent of 4 is 1. However, because you specified a MinAdjustmentMagnitude of 2, Amazon EC2 Auto Scaling scales out the group by 2 instances.

Valid only if the policy type is StepScaling or SimpleScaling. For more information, see Scaling adjustment types in the Amazon EC2 Auto Scaling User Guide.

Some Auto Scaling groups use instance weights. In this case, set the MinAdjustmentMagnitude to a value that is at least as large as your largest instance weight.

Available for backward compatibility. Use MinAdjustmentMagnitude instead.

Specifies how the scaling adjustment is interpreted (for example, an absolute number or a percentage). The valid values are ChangeInCapacity, ExactCapacity, and PercentChangeInCapacity.

Required if the policy type is StepScaling or SimpleScaling. For more information, see Scaling adjustment types in the Amazon EC2 Auto Scaling User Guide.

One of the following policy types:

• TargetTrackingScaling
• StepScaling
• SimpleScaling (default)
• PredictiveScaling

The name of the policy.

The name of the Auto Scaling group.

The CloudWatch alarms created for the target tracking scaling policy.

The Amazon Resource Name (ARN) of the policy.

The type of event that causes the notification to be sent. To query the notification types supported by Amazon EC2 Auto Scaling, call the DescribeAutoScalingNotificationTypes API.

The Amazon Resource Name (ARN) of the Amazon SNS topic.

The name of the Auto Scaling group.

The action the Auto Scaling group takes when the lifecycle hook timeout elapses or if an unexpected failure occurs. The default value is ABANDON.

Valid values: CONTINUE | ABANDON

The maximum time, in seconds, that can elapse before the lifecycle hook times out. The range is from 30 to 7200 seconds. The default value is 3600 seconds (1 hour).

Additional information that you want to include any time Amazon EC2 Auto Scaling sends a message to the notification target.

The Amazon Resource Name (ARN) of the notification target that Amazon EC2 Auto Scaling uses to notify you when an instance is in a wait state for the lifecycle hook. You can specify either an Amazon SNS topic or an Amazon SQS queue.

If you specify an empty string, this overrides the current ARN.

This operation uses the JSON format when sending notifications to an Amazon SQS queue, and an email key-value pair format when sending notifications to an Amazon SNS topic.

When you specify a notification target, Amazon EC2 Auto Scaling sends it a test message. Test messages contain the following additional key-value pair: "Event": "autoscaling:TEST_NOTIFICATION".

The ARN of the IAM role that allows the Auto Scaling group to publish to the specified notification target.

Valid only if the notification target is an Amazon SNS topic or an Amazon SQS queue. Required for new lifecycle hooks, but optional when updating existing hooks.

The lifecycle transition. For Auto Scaling groups, there are two major lifecycle transitions.

• To create a lifecycle hook for scale-out events, specify autoscaling:EC2_INSTANCE_LAUNCHING.
• To create a lifecycle hook for scale-in events, specify autoscaling:EC2_INSTANCE_TERMINATING.

Required for new lifecycle hooks, but optional when updating existing hooks.

The name of the Auto Scaling group.

The name of the lifecycle hook.

One of the following processes:

• Launch
• Terminate
• AddToLoadBalancer
• AlarmNotification
• AZRebalance
• HealthCheck
• InstanceRefresh
• ReplaceUnhealthy
• ScheduledActions

The names of the process types.

A string that indicates that the response contains more items than can be returned in a single response. To receive additional items, specify this string for the NextToken value when requesting the next set of items. This value is null when there are no more items to return.

The scaling policies.

One of the following event notification types:

• autoscaling:EC2_INSTANCE_LAUNCH
• autoscaling:EC2_INSTANCE_LAUNCH_ERROR
• autoscaling:EC2_INSTANCE_TERMINATE
• autoscaling:EC2_INSTANCE_TERMINATE_ERROR
• autoscaling:TEST_NOTIFICATION

The Amazon Resource Name (ARN) of the Amazon SNS topic.

The name of the Auto Scaling group.

The granularity. The only valid value is 1Minute.

One of the following metrics:

• GroupMinSize
• GroupMaxSize
• GroupDesiredCapacity
• GroupInServiceInstances
• GroupPendingInstances
• GroupStandbyInstances
• GroupTerminatingInstances
• GroupTotalInstances
• GroupInServiceCapacity
• GroupPendingCapacity
• GroupStandbyCapacity
• GroupTerminatingCapacity
• GroupTotalCapacity
• WarmPoolDesiredCapacity
• WarmPoolWarmedCapacity
• WarmPoolPendingCapacity
• WarmPoolTerminatingCapacity
• WarmPoolTotalCapacity
• GroupAndWarmPoolDesiredCapacity
• GroupAndWarmPoolTotalCapacity

The metric specification for the load forecast.

The values of the data points.

The timestamps for the data points, in UTC format.

The state of the target group.

• Adding - The Auto Scaling instances are being registered with the target group.
• Added - All Auto Scaling instances are registered with the target group.
• InService - At least one Auto Scaling instance passed an ELB health check.
• Removing - The Auto Scaling instances are being deregistered from the target group. If connection draining is enabled, Elastic Load Balancing waits for in-flight requests to complete before deregistering the instances.
• Removed - All Auto Scaling instances are deregistered from the target group.

The Amazon Resource Name (ARN) of the target group.