What is Backup
Creating data copies for recovery
Backup
Backup — the process of creating data copies for recovery in case of loss, damage, or attack.
Why Backup is Needed
| Threat | Protection | |--------|------------| | Hardware failure | Recovery from another media | | Human error | Rollback to previous version | | Viruses/ransomware | Clean copy without infection | | Natural disasters | Copy in different location |
Backup Types
- Full — copy of all data, large volume
- Incremental — only changes, fast but complex recovery
- Differential — changes from full, balance of speed and simplicity
- Synthetic — merging increments into full copy
Storage Locations
| Type | Pros | Cons | |------|------|------| | Local disk | Fast | Risk from fire/theft | | NAS/SAN | Reliable | Requires setup | | Cloud | Fault-tolerant | Depends on internet | | Tape | Cheap, durable | Slow access |
Backup Metrics
- RPO — maximum data loss (hours/days)
- RTO — recovery time
- Retention — copy storage duration
Tools
- Veeam — virtualization and cloud
- Acronis — universal solution
- Duplicati — free software
- rsync — Linux synchronization