Snapshot
A snapshot is a point-in-time copy of an EBS volume. Snapshots are incremental backups, which means that only the blocks on the device that have changed after your most recent snapshot are saved. This minimizes the time required to create the snapshot and saves on storage costs by not duplicating data.
Features of snapshots
- Snapshots are stored in Amazon S3.
- Snapshots are specific to the region in which they are created.
- Snapshots are encrypted by default using the AWS Key Management Service (KMS).
- You can share snapshots with other AWS accounts or make them public.
- You can create a new EBS volume from a snapshot and attach it to an instance even as a boot volume.
Creating a snapshot
- Open the Amazon EC2 console at https://console.aws.amazon.com/ec2/ (opens in a new tab).
- In the navigation pane, choose Volumes.
- Select the volume from which you want to create a snapshot.
- Choose Actions, Create snapshot.
- Enter a Name and Description for the snapshot.
- Choose Create snapshot.
AMI vs. snapshot
| AMI (Amazon Machine Image) | Snapshot |
|---|---|
| An AMI provides the information required to launch an instance. | A snapshot is a point-in-time copy of an EBS volume. |
| An AMI acts as an ISO file for the instance that is going to be launched. | Snapshots are incremental backups. |
| You must specify an AMI when you launch an instance. | You can create a new EBS volume from a snapshot and attach it to an instance. |
| You can launch multiple instances from a single AMI when you need multiple instances with the same configuration. | You can share snapshots with other AWS accounts or make them public. |
| You can use different AMIs to launch instances when you need instances with different configurations. | Snapshots are stored in Amazon S3. |
| AMI are not encrypted by default | Snapshots are encrypted by default using the AWS Key Management Service (KMS). |