Having said that, the ISO image is around 700MB So my preference is to understand how I go about converting an ISO to a VMDK, and then try to do that within a VMware VM, as I think that is most likely to meet all the stated pre-req's as I understand them. The Official AWS documentation specifically recommends using VMware to create the VMDK image. That link I posted indicates that not all vmdk images are equal (i.e. So in answer to your question - I don't really know. I just want to try and minimise the amount of error. To be frank the info on the process seems limited and as a result there is probably going to be some 'trial and error' on my part. I've looked at some YouTube videos and stuff I've found via Google to try and understand the process. A newbie when it comes to building a custom AMI (AWS Machine Image).