Successive Snapshots Have Same Size of Original Snapshot and Volume

Question

**Points of My Scenario:**

**1.** AWS documentation says snapshots are incremental backups: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/EBSSnapshots.html (2nd sentence).

**2.** I created 3 snapshots of an EC2 instance (in-between changes), using AWS procedures in https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ebs-creating-snapshot.html.

**3.** After each snapshot I created small changes: change-1 = create a user; change-2 = create a group and place user in the group.

**4.** However, each snapshot had the same size as the EC2 instance's volume.

**Question: **why are my successive snapshots all the same size as the EC2 instance's volume?

Accepted Answer

Hi There

The size of the snapshot that you see in the console is the size of the EBS volume.  The actual amount of the data that you are billed for is not shown, and there is no simple way to see the actual size.  However you are only billed for the incremental blocks stored in each snapshot.

From https://aws.amazon.com/ebs/pricing/

> Snapshot storage is based on the amount of space your data consumes in Amazon Simple Storage Service (Amazon S3). Because Amazon EBS does not save empty blocks, it is likely that the snapshot size will be considerably less than your volume size. For the first snapshot of a volume, Amazon EBS saves a full copy of your data to Amazon S3. For each incremental snapshot, only the changed part of your Amazon EBS volume is saved.

Also see this article for a graphical depiction on how incremental snapshots work: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/EBSSnapshots.html#how_snapshots_work

Successive Snapshots Have Same Size of Original Snapshot and Volume

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