error searching for detached instances for autoscaling group

Error message

error searching for detached instances for autoscaling group %q: %v

What it means

During ASG deletion, findDetachedInstances failed to list instances tagged as detached from the autoscaling group; the EC2 describe call errored and the wrapped AWS error explains the failure.

Source

Thrown at upup/pkg/fi/cloudup/awsup/aws_cloud.go:401

	return deleteGroup(ctx, c, g)
}

func deleteGroup(ctx context.Context, c AWSCloud, g *cloudinstances.CloudInstanceGroup) error {
	asg := g.Raw.(*autoscalingtypes.AutoScalingGroup)

	name := aws.ToString(asg.AutoScalingGroupName)
	template := aws.ToString(asg.LaunchConfigurationName)
	launchTemplate := ""
	if asg.LaunchTemplate != nil {
		launchTemplate = aws.ToString(asg.LaunchTemplate.LaunchTemplateName)
	}

	// Delete detached instances
	{
		detached, err := findDetachedInstances(ctx, c, asg)
		if err != nil {
			return fmt.Errorf("error searching for detached instances for autoscaling group %q: %v", name, err)
		}
		if len(detached) > 0 {
			klog.V(2).Infof("Deleting detached instances for autoscaling group %q", name)
			req := &ec2.TerminateInstancesInput{
				InstanceIds: detached,
			}
			if _, err := c.EC2().TerminateInstances(ctx, req); err != nil {
				return fmt.Errorf("error deleting detached instances for autoscaling group %q: %v", name, err)
			}
		}
	}

	// Delete ASG
	{
		klog.V(2).Infof("Deleting autoscaling group %q", name)
		request := &autoscaling.DeleteAutoScalingGroupInput{
			AutoScalingGroupName: aws.String(name),
			ForceDelete:          aws.Bool(true),

View on GitHub (pinned to 4c8573c808)

Solutions

Check EC2 describe permissions for the credentials in use
Retry the delete operation for transient API errors

Defensive patterns

Strategy: try-catch

When it happens

Trigger: Thrown at upup/pkg/fi/cloudup/awsup/aws_cloud.go:401 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of kubernetes/kops@4c8573c808 (2026-09-05). Data as JSON: /api/errors/39a49ab13d5313ea. Report an issue: GitHub.