I based my autoscaling AMI's on the Turnkey Linux nginx AMI from the marketplace.
I am now unable to select any of the newer generation instance types; for instance, my autoscaling uses m3.large type but I'd really like it to use the c3.xlarge type but every time I try to create a c3.xlarge instance with my AMI I get errors;
The instance configuration for this AWS Marketplace product is not supported.
My question is; Can I override this? I'm not using TKL support or any of their services, just the AMI.
If I can't override it, do I have any other options besides creating a brand new AMI from scratch to use?
File a bug report with them, asking them to make the AMI available for all instance types. It should be in their best interest to allow that.
Failing that, you can check what packages are installed and make a qualified guess regarding which configuration files they have paid any real attention to (nginx and related web things come to mind!) and copy those over to a custom-made AMI.
The first option is of course infinitely better, and helps them develop their product further.