I've inherited a Map Server that's implemented on AWS using EC2. ArcGIS Help mentions 'When you first create the cache, you'll write it to an EBS volume that's attached to your EC2 instance. This volume is attached at the time you build your site, and it's a good place to put the cache if the volume is large enough. If the volume is too small, you need to create and attach another volume and register a server cache directory on it.". The original implementation did not follow this advice, and when I share the map as a service it is done on the C: drive.
