interface AutoScalingGroupProps
Language | Type name |
---|---|
.NET | Amazon.CDK.AWS.AutoScaling.AutoScalingGroupProps |
Go | github.com/aws/aws-cdk-go/awscdk/v2/awsautoscaling#AutoScalingGroupProps |
Java | software.amazon.awscdk.services.autoscaling.AutoScalingGroupProps |
Python | aws_cdk.aws_autoscaling.AutoScalingGroupProps |
TypeScript (source) | aws-cdk-lib » aws_autoscaling » AutoScalingGroupProps |
Properties of a Fleet.
Example
declare const vpc: ec2.Vpc;
declare const instanceType: ec2.InstanceType;
declare const machineImage: ec2.IMachineImage;
new autoscaling.AutoScalingGroup(this, 'ASG', {
vpc,
instanceType,
machineImage,
// ...
init: ec2.CloudFormationInit.fromElements(
ec2.InitFile.fromString('/etc/my_instance', 'This got written during instance startup'),
),
signals: autoscaling.Signals.waitForAll({
timeout: Duration.minutes(10),
}),
});
Properties
Name | Type | Description |
---|---|---|
vpc | IVpc | VPC to launch these instances in. |
allow | boolean | Whether the instances can initiate connections to anywhere by default. |
associate | boolean | Whether instances in the Auto Scaling Group should have public IP addresses associated with them. |
auto | string | The name of the Auto Scaling group. |
block | Block [] | Specifies how block devices are exposed to the instance. You can specify virtual devices and EBS volumes. |
capacity | boolean | Indicates whether Capacity Rebalancing is enabled. |
cooldown? | Duration | Default scaling cooldown for this AutoScalingGroup. |
default | Duration | The amount of time, in seconds, until a newly launched instance can contribute to the Amazon CloudWatch metrics. |
desired | number | Initial amount of instances in the fleet. |
group | Group [] | Enable monitoring for group metrics, these metrics describe the group rather than any of its instances. |
health | Health | Configuration for health checks. |
ignore | boolean | If the ASG has scheduled actions, don't reset unchanged group sizes. |
init? | Cloud | Apply the given CloudFormation Init configuration to the instances in the AutoScalingGroup at startup. |
init | Apply | Use the given options for applying CloudFormation Init. |
instance | Monitoring | Controls whether instances in this group are launched with detailed or basic monitoring. |
instance | Instance | Type of instance to launch. |
key | string | Name of SSH keypair to grant access to instances. |
launch | ILaunch | Launch template to use. |
machine | IMachine | AMI to launch. |
max | number | Maximum number of instances in the fleet. |
max | number | Specifies the upper threshold as a percentage of the desired capacity of the Auto Scaling group. |
max | Duration | The maximum amount of time that an instance can be in service. |
min | number | Minimum number of instances in the fleet. |
min | number | Specifies the lower threshold as a percentage of the desired capacity of the Auto Scaling group. |
mixed | Mixed | Mixed Instances Policy to use. |
new | boolean | Whether newly-launched instances are protected from termination by Amazon EC2 Auto Scaling when scaling in. |
notifications? | Notification [] | Configure autoscaling group to send notifications about fleet changes to an SNS topic(s). |
require | boolean | Whether IMDSv2 should be required on launched instances. |
role? | IRole | An IAM role to associate with the instance profile assigned to this Auto Scaling Group. |
security | ISecurity | Security group to launch the instances in. |
signals? | Signals | Configure waiting for signals during deployment. |
spot | string | The maximum hourly price (in USD) to be paid for any Spot Instance launched to fulfill the request. |
ssm | boolean | Add SSM session permissions to the instance role. |
termination | Termination [] | A policy or a list of policies that are used to select the instances to terminate. |
termination | string | A lambda function Arn that can be used as a custom termination policy to select the instances to terminate. |
update | Update | What to do when an AutoScalingGroup's instance configuration is changed. |
user | User | Specific UserData to use. |
vpc | Subnet | Where to place instances within the VPC. |
vpc
Type:
IVpc
VPC to launch these instances in.
allowAllOutbound?
Type:
boolean
(optional, default: true)
Whether the instances can initiate connections to anywhere by default.
associatePublicIpAddress?
Type:
boolean
(optional, default: Use subnet setting.)
Whether instances in the Auto Scaling Group should have public IP addresses associated with them.
launchTemplate
and mixedInstancesPolicy
must not be specified when this property is specified
autoScalingGroupName?
Type:
string
(optional, default: Auto generated by CloudFormation)
The name of the Auto Scaling group.
This name must be unique per Region per account.
blockDevices?
Type:
Block
[]
(optional, default: Uses the block device mapping of the AMI)
Specifies how block devices are exposed to the instance. You can specify virtual devices and EBS volumes.
Each instance that is launched has an associated root device volume, either an Amazon EBS volume or an instance store volume. You can use block device mappings to specify additional EBS volumes or instance store volumes to attach to an instance when it is launched.
launchTemplate
and mixedInstancesPolicy
must not be specified when this property is specified
See also: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/block-device-mapping-concepts.html
capacityRebalance?
Type:
boolean
(optional, default: false)
Indicates whether Capacity Rebalancing is enabled.
When you turn on Capacity Rebalancing, Amazon EC2 Auto Scaling attempts to launch a Spot Instance whenever Amazon EC2 notifies that a Spot Instance is at an elevated risk of interruption. After launching a new instance, it then terminates an old instance.
cooldown?
Type:
Duration
(optional, default: Duration.minutes(5))
Default scaling cooldown for this AutoScalingGroup.
defaultInstanceWarmup?
Type:
Duration
(optional, default: None)
The amount of time, in seconds, until a newly launched instance can contribute to the Amazon CloudWatch metrics.
This delay lets an instance finish initializing before Amazon EC2 Auto Scaling aggregates instance metrics, resulting in more reliable usage data. Set this value equal to the amount of time that it takes for resource consumption to become stable after an instance reaches the InService state.
To optimize the performance of scaling policies that scale continuously, such as target tracking and step scaling policies, we strongly recommend that you enable the default instance warmup, even if its value is set to 0 seconds
Default instance warmup will not be added if no value is specified
See also: https://docs.aws.amazon.com/autoscaling/ec2/userguide/ec2-auto-scaling-default-instance-warmup.html
desiredCapacity?
Type:
number
(optional, default: minCapacity, and leave unchanged during deployment)
Initial amount of instances in the fleet.
If this is set to a number, every deployment will reset the amount of instances to this number. It is recommended to leave this value blank.
groupMetrics?
Type:
Group
[]
(optional, default: no group metrics will be reported)
Enable monitoring for group metrics, these metrics describe the group rather than any of its instances.
To report all group metrics use GroupMetrics.all()
Group metrics are reported in a granularity of 1 minute at no additional charge.
healthCheck?
Type:
Health
(optional, default: HealthCheck.ec2 with no grace period)
Configuration for health checks.
ignoreUnmodifiedSizeProperties?
Type:
boolean
(optional, default: true)
If the ASG has scheduled actions, don't reset unchanged group sizes.
Only used if the ASG has scheduled actions (which may scale your ASG up or down regardless of cdk deployments). If true, the size of the group will only be reset if it has been changed in the CDK app. If false, the sizes will always be changed back to what they were in the CDK app on deployment.
init?
Type:
Cloud
(optional, default: no CloudFormation init)
Apply the given CloudFormation Init configuration to the instances in the AutoScalingGroup at startup.
If you specify init
, you must also specify signals
to configure
the number of instances to wait for and the timeout for waiting for the
init process.
initOptions?
Type:
Apply
(optional, default: default options)
Use the given options for applying CloudFormation Init.
Describes the configsets to use and the timeout to wait
instanceMonitoring?
Type:
Monitoring
(optional, default: Monitoring.DETAILED)
Controls whether instances in this group are launched with detailed or basic monitoring.
When detailed monitoring is enabled, Amazon CloudWatch generates metrics every minute and your account is charged a fee. When you disable detailed monitoring, CloudWatch generates metrics every 5 minutes.
launchTemplate
and mixedInstancesPolicy
must not be specified when this property is specified
instanceType?
Type:
Instance
(optional, default: Do not provide any instance type)
Type of instance to launch.
launchTemplate
and mixedInstancesPolicy
must not be specified when this property is specified
keyName?
Type:
string
(optional, default: No SSH access will be possible.)
Name of SSH keypair to grant access to instances.
launchTemplate
and mixedInstancesPolicy
must not be specified when this property is specified
launchTemplate?
Type:
ILaunch
(optional, default: Do not provide any launch template)
Launch template to use.
Launch configuration related settings and MixedInstancesPolicy must not be specified when a launch template is specified.
machineImage?
Type:
IMachine
(optional, default: Do not provide any machine image)
AMI to launch.
launchTemplate
and mixedInstancesPolicy
must not be specified when this property is specified
maxCapacity?
Type:
number
(optional, default: desiredCapacity)
Maximum number of instances in the fleet.
maxHealthyPercentage?
Type:
number
(optional, default: No instance maintenance policy.)
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 0 to 100. After it's set, both minHealthyPercentage
and maxHealthyPercentage
to
-1 will clear the previously set value.
Both or neither of 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.
maxInstanceLifetime?
Type:
Duration
(optional, default: none)
The maximum amount of time that an instance can be in service.
The maximum duration applies to all current and future instances in the group. As an instance approaches its maximum duration, it is terminated and replaced, and cannot be used again.
You must specify a value of at least 604,800 seconds (7 days). To clear a previously set value, leave this property undefined.
See also: https://docs.aws.amazon.com/autoscaling/ec2/userguide/asg-max-instance-lifetime.html
minCapacity?
Type:
number
(optional, default: 1)
Minimum number of instances in the fleet.
minHealthyPercentage?
Type:
number
(optional, default: No instance maintenance policy.)
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. After it's set, both minHealthyPercentage
and maxHealthyPercentage
to
-1 will clear the previously set value.
Both or neither of 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.
mixedInstancesPolicy?
Type:
Mixed
(optional, default: Do not provide any MixedInstancesPolicy)
Mixed Instances Policy to use.
Launch configuration related settings and Launch Template must not be specified when a MixedInstancesPolicy is specified.
newInstancesProtectedFromScaleIn?
Type:
boolean
(optional, default: false)
Whether newly-launched instances are protected from termination by Amazon EC2 Auto Scaling when scaling in.
By default, Auto Scaling can terminate an instance at any time after launch when scaling in an Auto Scaling Group, subject to the group's termination policy. However, you may wish to protect newly-launched instances from being scaled in if they are going to run critical applications that should not be prematurely terminated.
This flag must be enabled if the Auto Scaling Group will be associated with an ECS Capacity Provider with managed termination protection.
notifications?
Type:
Notification
[]
(optional, default: No fleet change notifications will be sent.)
Configure autoscaling group to send notifications about fleet changes to an SNS topic(s).
requireImdsv2?
Type:
boolean
(optional, default: false)
Whether IMDSv2 should be required on launched instances.
role?
Type:
IRole
(optional, default: A role will automatically be created, it can be accessed via the role
property)
An IAM role to associate with the instance profile assigned to this Auto Scaling Group.
The role must be assumable by the service principal ec2.amazonaws.com
:
launchTemplate
and mixedInstancesPolicy
must not be specified when this property is specified
Example
const role = new iam.Role(this, 'MyRole', {
assumedBy: new iam.ServicePrincipal('ec2.amazonaws.com')
});
securityGroup?
Type:
ISecurity
(optional, default: A SecurityGroup will be created if none is specified.)
Security group to launch the instances in.
launchTemplate
and mixedInstancesPolicy
must not be specified when this property is specified
signals?
Type:
Signals
(optional, default: Do not wait for signals)
Configure waiting for signals during deployment.
Use this to pause the CloudFormation deployment to wait for the instances
in the AutoScalingGroup to report successful startup during
creation and updates. The UserData script needs to invoke cfn-signal
with a success or failure code after it is done setting up the instance.
Without waiting for signals, the CloudFormation deployment will proceed as soon as the AutoScalingGroup has been created or updated but before the instances in the group have been started.
For example, to have instances wait for an Elastic Load Balancing health check before they signal success, add a health-check verification by using the cfn-init helper script. For an example, see the verify_instance_health command in the Auto Scaling rolling updates sample template:
spotPrice?
Type:
string
(optional, default: none)
The maximum hourly price (in USD) to be paid for any Spot Instance launched to fulfill the request.
Spot Instances are launched when the price you specify exceeds the current Spot market price.
launchTemplate
and mixedInstancesPolicy
must not be specified when this property is specified
ssmSessionPermissions?
Type:
boolean
(optional, default: false)
Add SSM session permissions to the instance role.
Setting this to true
adds the necessary permissions to connect
to the instance using SSM Session Manager. You can do this
from the AWS Console.
NOTE: Setting this flag to true
may not be enough by itself.
You must also use an AMI that comes with the SSM Agent, or install
the SSM Agent yourself. See
Working with SSM Agent
in the SSM Developer Guide.
terminationPolicies?
Type:
Termination
[]
(optional, default: TerminationPolicy.DEFAULT
)
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.
See also: https://docs.aws.amazon.com/autoscaling/ec2/userguide/as-instance-termination.html
terminationPolicyCustomLambdaFunctionArn?
Type:
string
(optional, default: No lambda function Arn will be supplied)
A lambda function Arn that can be used as a custom termination policy to select the instances to terminate.
This property must be specified if the TerminationPolicy.CUSTOM_LAMBDA_FUNCTION is used.
See also: https://docs.aws.amazon.com/autoscaling/ec2/userguide/lambda-custom-termination-policy.html
updatePolicy?
Type:
Update
(optional, default: UpdatePolicy.rollingUpdate()
if using init
, UpdatePolicy.none()
otherwise)
What to do when an AutoScalingGroup's instance configuration is changed.
This is applied when any of the settings on the ASG are changed that affect how the instances should be created (VPC, instance type, startup scripts, etc.). It indicates how the existing instances should be replaced with new instances matching the new config. By default, nothing is done and only new instances are launched with the new config.
userData?
Type:
User
(optional, default: A UserData object appropriate for the MachineImage's
Operating System is created.)
Specific UserData to use.
The UserData may still be mutated after creation.
launchTemplate
and mixedInstancesPolicy
must not be specified when this property is specified
vpcSubnets?
Type:
Subnet
(optional, default: All Private subnets.)
Where to place instances within the VPC.