CfnAutoScalingInstanceRefreshPreferences

class aws_cdk.CfnAutoScalingInstanceRefreshPreferences(*, alarm_specification=None, bake_time=None, checkpoint_delay=None, checkpoint_percentages=None, instance_warmup=None, max_healthy_percentage=None, min_healthy_percentage=None, scale_in_protected_instances=None, skip_matching=None, standby_instances=None)

Bases: object

Preferences for the AutoScalingInstanceRefresh update policy.

Parameters:

  • alarm_specification (Union[CfnAutoScalingInstanceRefreshAlarmSpecification, Dict[str, Any], None]) – The CloudWatch alarms to monitor during the instance refresh. If any alarm goes into ALARM state, the instance refresh fails.

  • bake_time (Union[int, float, None]) – The number of seconds after an instance refresh completes successfully before CloudFormation considers the update successful. Default: 0

  • checkpoint_delay (Union[int, float, None]) – The number of seconds to wait after a checkpoint is reached before continuing. Default: - 3600 seconds (1 hour), applied only when checkpointPercentages is set

  • checkpoint_percentages (Optional[Sequence[Union[int, float]]]) – Threshold values for each checkpoint in ascending order. Each number is a percentage of the total number of instances in the group. When the percentage of instances that have been replaced reaches a checkpoint, the refresh waits for the configured checkpoint delay before continuing. Default: - no checkpoints

  • instance_warmup (Union[int, float, None]) – The number of seconds to wait after a new instance enters the InService state before moving on to replacing the next instance. Default: - the group’s DefaultInstanceWarmup if defined; otherwise the group’s HealthCheckGracePeriod

  • max_healthy_percentage (Union[int, float, None]) – The maximum percentage of the group that can be in service and healthy, or pending, to support your workload during the instance refresh. Used to control batch size. Default: - the value set in the Auto Scaling group’s instance maintenance policy, if defined; otherwise 110 when the strategy is Rolling, or 100 when the strategy is ReplaceRootVolume

  • min_healthy_percentage (Union[int, float, None]) – The minimum percentage of the group to keep in service, healthy, and ready to use to support your workload during the instance refresh. Default: - the value set in the Auto Scaling group’s instance maintenance policy, if defined; otherwise 100 when the strategy is Rolling, or 90 when the strategy is ReplaceRootVolume

  • scale_in_protected_instances (Optional[str]) – Specifies the behavior of instances that are protected from scale in during an instance refresh. Default: ‘Wait’

  • skip_matching (Optional[bool]) – Indicates whether skip matching is enabled. If true, instances that already match the desired configuration are not replaced. Default: true

  • standby_instances (Optional[str]) – Specifies the behavior of instances in standby during an instance refresh. Default: ‘Wait’

ExampleMetadata:

fixture=_generated

Example:

# The code below shows an example of how to instantiate this type.
# The values are placeholders you should change.
import aws_cdk as cdk

cfn_auto_scaling_instance_refresh_preferences = cdk.CfnAutoScalingInstanceRefreshPreferences(
    alarm_specification=cdk.CfnAutoScalingInstanceRefreshAlarmSpecification(
        alarms=["alarms"]
    ),
    bake_time=123,
    checkpoint_delay=123,
    checkpoint_percentages=[123],
    instance_warmup=123,
    max_healthy_percentage=123,
    min_healthy_percentage=123,
    scale_in_protected_instances="scaleInProtectedInstances",
    skip_matching=False,
    standby_instances="standbyInstances"
)

Attributes

alarm_specification

The CloudWatch alarms to monitor during the instance refresh.

If any alarm goes into ALARM state, the instance refresh fails.

bake_time

The number of seconds after an instance refresh completes successfully before CloudFormation considers the update successful.

Default:

0

checkpoint_delay

The number of seconds to wait after a checkpoint is reached before continuing.

Default:

  • 3600 seconds (1 hour), applied only when checkpointPercentages is set

checkpoint_percentages

Threshold values for each checkpoint in ascending order.

Each number is a percentage of the total number of instances in the group. When the percentage of instances that have been replaced reaches a checkpoint, the refresh waits for the configured checkpoint delay before continuing.

Default:

  • no checkpoints

instance_warmup

The number of seconds to wait after a new instance enters the InService state before moving on to replacing the next instance.

Default:

  • the group’s DefaultInstanceWarmup if defined; otherwise the group’s HealthCheckGracePeriod

max_healthy_percentage

The maximum percentage of the group that can be in service and healthy, or pending, to support your workload during the instance refresh.

Used to control batch size.

Default:

  • the value set in the Auto Scaling group’s instance maintenance policy, if defined; otherwise 110 when the strategy is Rolling, or 100 when the strategy is ReplaceRootVolume

min_healthy_percentage

The minimum percentage of the group to keep in service, healthy, and ready to use to support your workload during the instance refresh.

Default:

  • the value set in the Auto Scaling group’s instance maintenance policy, if defined; otherwise 100 when the strategy is Rolling, or 90 when the strategy is ReplaceRootVolume

scale_in_protected_instances

Specifies the behavior of instances that are protected from scale in during an instance refresh.

Default:

‘Wait’

skip_matching

Indicates whether skip matching is enabled.

If true, instances that already match the desired configuration are not replaced.

Default:

true

standby_instances

Specifies the behavior of instances in standby during an instance refresh.

Default:

‘Wait’