Registers or updates a scalable target, which is the resource that you want to scale.
Scalable targets are uniquely identified by the combination of resource ID, scalable dimension, and namespace, which represents some capacity dimension of the underlying service.
When you register a new scalable target, you must specify values for the minimum and maximum capacity. If the specified resource is not active in the target service, this operation does not change the resource's current capacity. Otherwise, it changes the resource's current capacity to a value that is inside of this range.
If you add a scaling policy, current capacity is adjustable within the specified range when scaling starts. Application Auto Scaling scaling policies will not scale capacity to values that are outside of the minimum and maximum range.
After you register a scalable target, you do not need to register it again to use other Application Auto Scaling operations. To see which resources have been registered, use
DescribeScalableTargets. You can also view the scaling policies for a service namespace by using
DescribeScalableTargets. If you no longer need a scalable target, you can deregister it by using
DeregisterScalableTarget.
To update a scalable target, specify the parameters that you want to change. Include the parameters that identify the scalable target: resource ID, scalable dimension, and namespace. Any parameters that you don't specify are not changed by this update request.
If you call the
RegisterScalableTarget API operation to create a scalable target, there might be a brief delay until the operation achieves
eventual consistency. You might become aware of this brief delay if you get unexpected errors when performing sequential operations. The typical strategy is to retry the request, and some Amazon Web Services SDKs include automatic backoff and retry logic.
If you call the
RegisterScalableTarget API operation to update an existing scalable target, Application Auto Scaling retrieves the current capacity of the resource. If it's below the minimum capacity or above the maximum capacity, Application Auto Scaling adjusts the capacity of the scalable target to place it within these bounds, even if you don't include the
MinCapacity or
MaxCapacity request parameters.