Yes, this is a supported configuration, in that you can do it. But Adobe doesn't really provide any specific licenses that take a variable number of servers into account. Also, Adobe doesn't provide any EC2-specific licensing as far as I'm aware - EC2 instances are treated as physical servers for Adobe licensing purposes. There are two licensing options that will ensure your compliance with licensing requirements. One is for you to simply purchase as many CF licenses as you'd need for the maximum number of servers you'll have in the auto-scaling pool. This would mean you're paying more for CF licenses than you typically need at any given time, and you might have to buy more licenses if your maximum auto-scaling pool size increases over time.
The other option is to "rent" CF from a third party AMI provider. You'll pay a monthly cost for images created from this AMI that covers the licensing for CF, which is actually paid by the third party to Adobe. Since you're a Windows shop, this would work well for you as they only offer a Windows AMI. I don't recall the name of the company offhand - it just recently changed, I think - but if you search the AMI Marketplace for "ColdFusion" you'll find it. The AMI has ColdFusion already installed. There's no reason why you can't customize it, or even remove it and reinstall it yourself I guess, as long as you're paying the "rent" for the AMI itself. You can use this AMI to create your own custom AMI, but you will of course be billed the surcharge for the original AMI for those instances you create from your custom AMI.
Setting aside licensing, there are some other considerations for your migration. For example, you'll probably want to refactor your application so that it can use shared storage. You could use EFS if you were using Linux instead of Windows, but you'll probably find S3 a better solution in a Windows environment. This will let you simplify your base image and file storage quite a bit.
Dave Watts, Fig Leaf Software
AdChoices