Overview
This lecture covers strategies and best practices for data backups, including types of backups, restoration options, backup locations, and industry-standard backup schedules.
Backup Strategies and Considerations
- Always have a backup strategy to prevent data loss or corruption.
- Consider total data size, backup type, media, storage location, software, and backup frequency.
Types of Backups
- Full Backup: Copies all system data; time- and storage-intensive but fastest to restore.
- Differential Backup: First backup is full, subsequent backups save changes since the last full; moderate time and storage needs.
- Incremental Backup: First backup is full, then only changes since the last backup each time; fast backups, but restores require all incrementals.
- Synthetic Backup: Combines existing full and incremental/differential backups to create a new full backup without transferring all data again.
Backup and Restoration Processes
- Always test restoration to ensure backup integrity and process reliability.
- Restoration can be in-place (overwriting original files) or to an alternate location (to avoid overwriting).
Backup Locations
- On-site Backup: Data is stored locally; fast access, but vulnerable to local disasters.
- Off-site Backup: Data is stored remotely; protects against local site failure.
Backup Scheduling Strategies
- Grandfather-Father-Son (GFS): Grandfather = monthly full backups, Father = weekly backups, Son = daily backups for comprehensive layering.
The 3-2-1 Backup Rule
- Keep three copies of backup data.
- Store backups on at least two different media types.
- Ensure at least one backup copy is off-site.
Key Terms & Definitions
- Full Backup — A complete copy of all system data.
- Differential Backup — Backs up changes since the last full backup.
- Incremental Backup — Backs up changes since the last backup (full or incremental).
- Synthetic Backup — Combines existing backups to form a new full backup.
- GFS (Grandfather-Father-Son) — A layered backup rotation schedule.
- 3-2-1 Rule — A guideline for backup redundancy and diversity.
Action Items / Next Steps
- Simulate a recovery test by restoring a specific file to confirm backup integrity.
- Regularly audit backup and restoration processes.
- Implement or review GFS and/or 3-2-1 backup strategies for your systems.