Root Device on SSD instance types. SSD vs EBS confusion

I have an AMI that was originally created from a t1.micro linux. The "Root Device Type" of this AMI is EBS (8 GB) and my web application software is "baked" into this root volume.

Now I would like to launch an m3.medium instance from this AMI but it has "Instance Storage" of 4GB SSD.

Will my newly launched m3.medium instance take advantage of the SSD storage at all? Or do I need to create a new AMI with "Instance Store" as the root "Root Device Type"?

Similarly ... When I try to launch an m3.medium from scratch using the "Amazon Linux AMI 2013.09.2" it adds an 8GB Root EBS volume by default that cannot be removed using the launch wizard.

What am I missing here?

Solution 1:

Regardless of what it has as instance storage, it'll boot off an EBS drive. You can mount the SSD as an additional drive - this can be handy for swap space, temporary files, caches, etc.

Solution 2:

Worth noting for future readers Amazon made 'general purpose' SSDs available across EBS. You can select then via the console, or via the apis as 'gp2'. They're a few cents a month more expensive than standard magnetic drives.

http://aws.amazon.com/blogs/aws/new-ssd-backed-elastic-block-storage/ http://aws.amazon.com/ebs/details/