Isso é por design e documentado na AWS :: AutoScaling: : Guia do usuário LaunchConfiguration :
Important
When you update a LaunchConfiguration resource, AWS CloudFormation will delete that resource and create a new one with the updated properties and a new name. This update action does not deploy any change across the running EC2 instances in the auto scaling group. In other words, an update simply replaces the LaunchConfiguration so that when the auto scaling group launches new instances, they will get the updated configuration, but existing instances will continue to run with the configuration that they were originally launched with. This works the same way as if you made similar changes manually to an auto scaling group.
Eu recomendo que, em sua pilha de testes, você crie o modelo exatamente como você tem para produção, apenas ajuste os valores para reduzir o custo, por exemplo, MinSize
, MaxSize
e DesiredCapacity
são 1, etc.