Cloud Computing
Backup
Definition
A backup is a copy of computer data taken and stored elsewhere so that it may be used to restore the original after a data loss event. Backups are a critical part of a disaster recovery strategy.
Why It Matters
Backups protect against data loss due to hardware failure, human error, malware, or natural disasters. Without backups, a single event could permanently destroy valuable or irreplaceable data.
Contextual Example
A common strategy is the 3-2-1 backup rule: have at least three copies of your data, on two different types of media, with one copy stored off-site. Cloud storage services like AWS S3 or Glacier are often used for the off-site copy.
Common Misunderstandings
- A backup is not the same as high availability or redundancy. Redundancy protects against downtime, while a backup protects against data loss.
- Backups need to be tested regularly to ensure they can be successfully restored when needed.