AWS EBS Snapshot Explained
Amazon Elastic Block Store (Amazon EBS) is a service that provides persistent block-level storage for Amazon Elastic Compute Cloud (Amazon EC2) instances. Simply speaking, the service allocates reliable hard drives (aka volumes) to cloud servers. One of the very useful features of Amazon EBS is creating snapshots of EBS volumes. According to Amazon Knowledge Base, AWS EBS snapshots are backups of EBS volumes. But are they indeed backups? Let’s find out how EBS snapshots work, and what they can do.
What is EBS Snapshot?
An EBS snapshot is a point-in-time copy of your Amazon EBS volume, which is lazily copied to Amazon Simple Storage Service (Amazon S3). EBS snapshots are incremental copies of data. This means that only unique blocks of EBS volume data that have changed since the last EBS snapshot are stored in the next EBS snapshot. This is how incremental copies of data are created in Amazon AWS EBS Snapshot.
Each AWS snapshot contains all the information needed to restore your data starting from the moment of creating the EBS snapshot. EBS snapshots are chained together. By using them, you will be able to properly restore your EBS volumes, when needed.
Deletion of an EBS snapshot is a process of removing only the data related to that specific snapshot. Therefore, you can safely delete any old snapshots with no harm. If you delete an old snapshot, AWS will consolidate the snapshot data: all valid data will be moved forward to the next snapshot and all invalid data will be discarded.
Read the entire article here, AWS EBS Snapshot Explained
via the fine folks at NAKIVO.