EC2: How to tell if disk volume is instance store or EBS?

Question

I have a number of volumes (same size) attached to a Windows EC2 instance in Amazon AWS.

One of them is told to be an instance store, the rest are EBS.

How do I tell which one is the instance store? They all look the same in Device Manager - "XENSRC PVDISK SCSI Disk Device"

PS. testing the speed did not help, one of the drives IS slightly faster than the others but how I can be sure it's an instance store?

Answer 1

I just got done doing this with unix servers in Ansible last week! Here are the block devices that are instance stores on Windows. If you want to see which ones are actually available, look for entries in the block-device-mapping. I'm showing the following with curl and a Linux host because it's easier to illustrate:

$ curl http://169.254.169.254/2014-02-25/meta-data/block-device-mapping/
ami
ephemeral0
$ curl http://169.254.169.254/2014-02-25/meta-data/block-device-mapping/ephemeral0
sdb

In this case, sdb (or xvdb) is an instance-store.

Here are some further links:

• How to add swap to and Amazon EC2 instance running Ubuntu 12.04 LTS?
• https://gist.github.com/joemiller/6049831