[msolson]

Instance storage can be a good option depending on your workload, but definitely has limitations. There's huge value in separating the lifecycle of storage from compute, and EBS provides higher durability than instance storage as well.

There are no operating system limitations that I'm aware of, however. I was just able to launch a Windows m6idn.2xlarge to verify.

[ayewo]

Thanks for checking. I realize now that I wasn’t clear in my original comment.

My use case was to bring up a Windows instance using instance storage as the root device instead using of EBS which is the default root device.

I wanted to run some benchmarks directly on drive C:\ — backed by an NVMe SSD-based instance store — because of an app that will only install to drive C:\, but it seems there’s no way to do this.

The EC2 docs definitely gave me the impression that instance storage is not supported on Windows as a root volume.

Here’s one such note from the docs: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/RootDevi...

”Windows instances do not support instance-store backed root volumes.”

Really nice that you are engaging with the comments here on HN as the article’s author.

(For others who may not be aware, msolson = Marc Olson)

[msolson]

Ah yes. Instance store root volumes are what we originally launched EC2 with--EBS came along 2 years later, but as data volumes only at first, with boot from EBS I think a year after that. There's a lot less fragility, and really it's just easier for our customers to create an EBS snapshot based AMI.

Before we launched the c4 instance family the vast majority of instance launches were from EBS backed AMIs, so we decided to remove a pile of complexity, and beginning with the c4 instance family, we stopped supporting instance storage root volumes on new instance families.