:doc:`AutoScaling <../../autoscaling>` / Client / attach_load_balancers

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attach_load_balancers
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.. py:method:: AutoScaling.Client.attach_load_balancers(**kwargs)

  

  .. note::

    

    This API operation is superseded by `AttachTrafficSources <https://docs.aws.amazon.com/autoscaling/ec2/APIReference/API_AttachTrafficSources.html>`__, which can attach multiple traffic sources types. We recommend using ``AttachTrafficSources`` to simplify how you manage traffic sources. However, we continue to support ``AttachLoadBalancers``. You can use both the original ``AttachLoadBalancers`` API operation and ``AttachTrafficSources`` on the same Auto Scaling group.

    

   

  Attaches one or more Classic Load Balancers to the specified Auto Scaling group. Amazon EC2 Auto Scaling registers the running instances with these Classic Load Balancers.

   

  To describe the load balancers for an Auto Scaling group, call the `DescribeLoadBalancers <https://docs.aws.amazon.com/autoscaling/ec2/APIReference/API_DescribeLoadBalancers.html>`__ API. To detach a load balancer from the Auto Scaling group, call the `DetachLoadBalancers <https://docs.aws.amazon.com/autoscaling/ec2/APIReference/API_DetachLoadBalancers.html>`__ API.

   

  This operation is additive and does not detach existing Classic Load Balancers or target groups from the Auto Scaling group.

   

  For more information, see `Use Elastic Load Balancing to distribute traffic across the instances in your Auto Scaling group <https://docs.aws.amazon.com/autoscaling/ec2/userguide/autoscaling-load-balancer.html>`__ in the *Amazon EC2 Auto Scaling User Guide*.

  

  See also: `AWS API Documentation <https://docs.aws.amazon.com/goto/WebAPI/autoscaling-2011-01-01/AttachLoadBalancers>`_  


  **Request Syntax**
  ::

    response = client.attach_load_balancers(
        AutoScalingGroupName='string',
        LoadBalancerNames=[
            'string',
        ]
    )
    
  :type AutoScalingGroupName: string
  :param AutoScalingGroupName: **[REQUIRED]** 

    The name of the Auto Scaling group.

    

  
  :type LoadBalancerNames: list
  :param LoadBalancerNames: **[REQUIRED]** 

    The names of the load balancers. You can specify up to 10 load balancers.

    

  
    - *(string) --* 

    

  
  :rtype: dict
  :returns: 
    
    **Response Syntax**

    
    ::

      {}
      
    **Response Structure**

    

    - *(dict) --* 
  
  **Exceptions**
  
  *   :py:class:`AutoScaling.Client.exceptions.ResourceContentionFault`

  
  *   :py:class:`AutoScaling.Client.exceptions.ServiceLinkedRoleFailure`

  
  *   :py:class:`AutoScaling.Client.exceptions.InstanceRefreshInProgressFault`

  

  **Examples**

  This example attaches the specified load balancer to the specified Auto Scaling group.
  ::

    response = client.attach_load_balancers(
        AutoScalingGroupName='my-auto-scaling-group',
        LoadBalancerNames=[
            'my-load-balancer',
        ],
    )
    
    print(response)

  
  Expected Output:
  ::

    {
        'ResponseMetadata': {
            '...': '...',
        },
    }

  