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How to update an existing Amazon EBS snapshot without creating a new snapshot for new data in AWS?

For example, I have to 1 GB of data in 2 GB of EBS volume have created snapshot1 and shared to different regions of the same account. After some time have added 500 MB of data to my EBS volume so a total of 1.5 GB of data in 2 GB volume now..instead of creating new snapshot2 for 1.5 GB of data can update or attach 500mb of data to the existing snapshot1.

How to achieve this in AWS?

John Rotenstein
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devops practice
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1 Answers1

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It is not possible to "update" an Amazon EBS Snapshot.

You should create a new EBS Snapshot. You can then delete the old snapshot if you wish, or keep it around. You would be charged the same for storage either way.

An Amazon EBS Snapshot only contains the "changes" made to a disk. So, if you started with a completely blank disk and stored 1GB, then the first snapshot would consume 1GB.

If you then added or changed 500MB of data on the original EBS Volume and then made another snapshot, the additional 500MB of data would be copied to Amazon S3 (you can't see it, but that's where snapshots are stored). The 2nd snapshot would also point to the 1GB of data in the earlier snapshot. So, you would pay for 1.5GB of snapshot data.

If you then deleted the first snapshot, you would still be paying for 1.5GB of snapshot data because the 2nd snapshot is still using the original 1GB of data in Amazon S3.

Bottom line: Creating a new snapshot will effectively create an "updated" snapshot anyway. You are not paying for double-storage of the same data.

John Rotenstein
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  • i heard from someone we can achieve this using aws config service...can u tell me how aws config service is useful for ebs snapshots – devops practice Feb 15 '20 at 15:05
  • [AWS Config](https://docs.aws.amazon.com/config/latest/developerguide/WhatIsConfig.html) keeps a historical record of configuration changes of AWS resources. So, it can tell you _when_ you took a snapshot and _when_ it was deleted. It can tell you which volume it came from and the history of that volume, and even the history of the EC2 instance where it was attached. It cannot, however, influence the _content_ of an EBS Snapshot. (In fact, nothing can!) – John Rotenstein Feb 15 '20 at 21:58