All AMIs are either categorized as Amazon EBS or backed by an instance store.
For EBS volume – The root device for an instance launched from the AMI is an Amazon EBS volume created from an amazon EBS snapshot.
For Instances Store Volume – The root device is an instance launched from the AMI is an instance store volume created from a template stored in Amazon S3.
AMI can be selected based on
Region (Region and Availability zone)
Operating Systems
Architecture (32 and 64 bits)
Launch permission
Storage for root device (Root Device Volume)
Instance Store (Ephemeral Storage)
EBS backend volume
Operating System
AWS provides a variety of OS, which we can select and install as per our requirements.
Architecture Type
Root Device Type
EBS vs Instance Store
Instance store volumes are sometimes called Ephemeral storage.
Instance store volumes cannot be stopped You will lose the data on this instance if it is stopped.
The EBS-backed instances can be stopped, without data loss.
You can reboot both types of the Instance, without data loss.
Upon termination, both Root volumes will be deleted. But in EBS volumes, we can tell AWS to keep the root device volume.
