# AWS: Update ASG Configuration Values

Updates Auto Scaling Group settings such as minimum size, maximum size, desired capacity, or launch template version as needed.


> **Availability:** See the [Incident Workflow Actions Overview table](/workflow-actions) for the plans this workflow is available on.

## Description

**Premium.** This action is a Premium Workflow Action, billed separately from your PagerDuty plan. In the workflow action picker, this action appears as **Auto Scaling: Update Auto Scaling Group**.

Update Auto Scaling Group (ASG) configuration values such as min size, max size, desired capacity, or launch template. Only the fields you provide are changed; others are left unchanged. This action is useful for:

- Temporarily bumping max size during instance rotation so the ASG can launch a replacement before the old instance is terminated
- Scaling up desired capacity during a load incident (often combined with Describe Auto Scaling Groups to read current values first)
- Updating the launch template version for rolling updates or remediation
- Automating capacity changes in runbooks based on incident or prior-step outputs

## Instructions

1. If you have not done so, follow the instructions to [Create an Incident Workflow](/ai-automation/automation/incident-workflows#create-an-incident-workflow).
2. When the instructions prompt you to [add actions](/ai-automation/automation/incident-workflows#add-actions), select **this action**.
3. Enter the following **Inputs** and click **Save**.
4. Continue following instructions to **Publish** the Workflow.
5. When the action runs, you will see the **Outputs** listed below.

## Inputs

> **Field References:** Fields with the **\{+\}** icon accept [Field References](/ai-automation/automation/incident-workflows#field-references), which can be useful for referencing incident data or outputs created in prior workflow steps. To add Field References, click **\{+\}**, or enter `{{`, and select relevant fields. Refer to the [Field References](/ai-automation/automation/incident-workflows#field-references) article for more information.

| Name                    | Description                                                                                                                                                                   |
| :---------------------- | :---------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Integration             | Select a [Workflow Integration](/ai-automation/automation/incident-workflows/workflow-integrations) or click **New AWS Connection** to establish a new one.                        |
| Auto Scaling Group Name | The name of the Auto Scaling Group to update.                                                                                                                                 |
| AWS Region              | The AWS region where the Auto Scaling Group is located. If left blank, the action uses `us-east-1` as the default.                                                            |
| Minimum Size            | (Optional.) New minimum size. Omit to leave unchanged.                                                                                                                        |
| Maximum Size            | (Optional.) New maximum size. Omit to leave unchanged.                                                                                                                        |
| Desired Capacity        | (Optional.) New desired capacity. Omit to leave unchanged.                                                                                                                    |
| New Launch Template     | (Optional.) Launch template to switch to. Can include **Launch Template ID**, **Launch Template Name**, and **Version**. Omit to leave the current launch template unchanged. |

## Outputs

| Name           | Description                                                                                                    |
| :------------- | :------------------------------------------------------------------------------------------------------------- |
| ASG Name       | The Auto Scaling Group that was updated.                                                                       |
| Applied        | JSON object of the values that were sent (minSize, maxSize, desiredCapacity, launchTemplate) for auditability. |
| 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.                                                                           |

> **Tips:** - **Partial Updates**: Only include inputs you want to change; omitting Minimum Size, Maximum Size, Desired Capacity, or New Launch Template leaves those settings unchanged.
> - **Instance Rotation**: For rotate-instance workflows, use **Describe Auto Scaling Groups** and a Logic step first to compute the new max size, then pass it into this action's **Maximum Size** input.