Chapter 13: Amazon EBS (Elastic Block Store)
13.3 Snapshots
In short: A snapshot is a point-in-time backup of an EBS volume.
A snapshot is a point-in-time backup of an EBS volume.
- Incremental: the first snapshot copies all used blocks; later ones store only changed blocks (cheaper), yet each snapshot can restore the full volume.
- Regional: a snapshot can create volumes in any AZ of the region; you can copy it to another region (disaster recovery) and share it with other accounts.
- AMIs are built from snapshots of the root volume.
- Automation: Amazon Data Lifecycle Manager (DLM) or AWS Backup can create and delete snapshots on a schedule.
- Consistency: for databases, stop writes (or stop the instance / flush tables) before taking a snapshot to get an application-consistent backup.
Console: EC2 → Elastic Block Store → Volumes → select volume → Actions → Create snapshot → description/tag → Create snapshot. Restore: Snapshots → select → Actions → Create volume from snapshot → choose AZ (same as target instance), type, size.
AWS CLI equivalents (optional):
aws ec2 create-snapshot --volume-id vol-0123456789abcdef0 --description "before-upgrade"
aws ec2 describe-snapshots --owner-ids self --query "Snapshots[].[SnapshotId,VolumeId,StartTime,State]" --output table
aws ec2 create-volume --snapshot-id snap-0123456789abcdef0 --availability-zone ap-south-1a --volume-type gp3