Description

Enable or disable "Protected from scale-in" on selected instances in an Auto Scaling Group (ASG). When protection is enabled, the ASG will not terminate these instances during scale-in events, which is useful when you are about to move an instance to Standby or terminate it in a controlled way. This action is useful for:

Protecting an instance from scale-in before rotating it out of the ASG (e.g., before Enter Standby and Terminate)
Ensuring a specific instance is not chosen for termination during automatic scale-in
Building runbooks that combine with Describe Auto Scaling Instances, Enter Standby, and Terminate Instance in Auto Scaling Group for safe instance rotation
Temporarily shielding instances during maintenance or troubleshooting

Instructions

Inputs

Name	Description
Integration	Select a Workflow Integration or click New AWS Connection to establish a new one.
Auto Scaling Group Name	The name of the Auto Scaling Group that contains the instances.
Instance IDs	One or more EC2 instance IDs to set or clear protection for (comma-separated). Can be from a prior step (e.g., Describe Auto Scaling Instances) or from incident custom details.
AWS Region	The AWS region where the ASG is located. If left blank, the action uses `us-east-1` as the default.
Protected From Scale In	Set to true to protect the instances from scale-in (recommended before rotating an instance out). Set to false to remove protection.

Outputs

Name	Description
ASG Name	The Auto Scaling Group that was targeted.
Protected	Array of instance IDs that were set to the requested protection state.
Protected From Scale In	The protection value that was applied (true or false).
Result	Whether the action succeeded: Success or Failed.
Result Summary	Brief description of what the action did or if it failed.
Error	Error message, if the action failed.

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Tips

Instance Rotation: In a rotate-instance runbook, set Protected From Scale In = true before Enter Standby so the ASG does not select this instance for scale-in while you are rotating it out.

Chaining Actions: Use Auto Scaling Group Name and Instance IDs from Auto Scaling: Describe Auto Scaling Instances (e.g., instances[0].asgName, and the same instance IDs) so the workflow works when the incident only provides an instance ID.