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AWS EBS Incremental snapshot backup facts

AWS actually manages the metadata of snapshot backups. 

After writing data to an Amazon EBS volume, you can periodically create a snapshot of the volume to use as a baseline for new volumes or for data backup.

If you make periodic snapshots of a volume, the snapshots are incremental so that only the blocks on the device that have changed after your last snapshot are saved in the new snapshot.

Even though snapshots are saved incrementally, the snapshot deletion process is designed so that you need to retain only the most recent snapshot in order to restore the volume.

Example:

Create a file a.log on Monday and take a snapshot backup name - snap-monday

Create a second file b.log on Tuesday and take a snapshot backup name - snap-tuesday

Create the third file c.log on Wednesday and take a snapshot backup name - snap-wednesday

You don't need to retain all the three snapshots to restore back from latest snapshot (c.log ).

You can restore entire thing from the last snapshot backup.

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