AWS SDK Version 3 for .NET
API Reference

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Removes one or more instances from the specified Auto Scaling group.

After the instances are detached, you can manage them independent of the Auto Scaling group.

If you do not specify the option to decrement the desired capacity, Amazon EC2 Auto Scaling launches instances to replace the ones that are detached.

If there is a Classic Load Balancer attached to the Auto Scaling group, the instances are deregistered from the load balancer. If there are target groups attached to the Auto Scaling group, the instances are deregistered from the target groups.

For more information, see Detach EC2 Instances from Your Auto Scaling Group in the Amazon EC2 Auto Scaling User Guide.


For .NET Core and PCL this operation is only available in asynchronous form. Please refer to DetachInstancesAsync.

Namespace: Amazon.AutoScaling
Assembly: AWSSDK.AutoScaling.dll
Version: 3.x.y.z


public virtual DetachInstancesResponse DetachInstances(
         DetachInstancesRequest request
Type: Amazon.AutoScaling.Model.DetachInstancesRequest

Container for the necessary parameters to execute the DetachInstances service method.

Return Value
The response from the DetachInstances service method, as returned by AutoScaling.


ResourceContentionException You already have a pending update to an Auto Scaling resource (for example, a group, instance, or load balancer).


This example detaches the specified instance from the specified Auto Scaling group.

To detach an instance from an Auto Scaling group

var response = client.DetachInstances(new DetachInstancesRequest 
    AutoScalingGroupName = "my-auto-scaling-group",
    InstanceIds = new List {
    ShouldDecrementDesiredCapacity = true

List activities = response.Activities;


Version Information

.NET Framework:
Supported in: 4.5, 4.0, 3.5

Portable Class Library:
Supported in: Windows Store Apps
Supported in: Windows Phone 8.1
Supported in: Xamarin Android
Supported in: Xamarin iOS (Unified)
Supported in: Xamarin.Forms

See Also