Backup and Recovery Strategies
1. What are Backup and Recovery Strategies?
- Backup: Creating copies of data to protect against data loss.
- Recovery: Restoring data from backups after a failure or loss.
2. Types of Backup
- Full Backup
- Entire data is copied.
- Pros: Easy recovery.
- Cons: Time-consuming, requires more storage.
- Incremental Backup
- Only changes since the last backup are saved.
- Pros: Faster, saves storage.
- Cons: Slower recovery as all backups must be combined.
- Differential Backup
- Copies all changes since the last full backup.
- Pros: Faster recovery than incremental.
- Cons: Takes more space than incremental.
3. Backup Strategies
- 3-2-1 Rule
- 3 Copies of data.
- 2 Stored on different media (e.g., disk, tape).
- 1 Kept offsite (cloud or remote location).
- Daily, Weekly, Monthly (DWM) Backups
- Daily: Incremental backups.
- Weekly: Differential backups.
- Monthly: Full backups.
- Onsite and Offsite Backups
- Onsite: Quick recovery but vulnerable to disasters.
- Offsite: Protects against local disasters.
4. Recovery Strategies
- Cold Site
- Minimal setup; resources configured only after a disaster.
- Pros: Low cost.
- Cons: Slow recovery.
- Warm Site
- Partially set up with hardware/software; requires updates before use.
- Pros: Balanced cost and recovery time.
- Hot Site
- Fully functional, ready-to-use backup environment.
- Pros: Fast recovery.
- Cons: Expensive.
5. Key Backup and Recovery Tools
- Veeam Backup & Replication: Popular for virtual and physical backups.
- Acronis: Disk imaging and cloud backup.
- Commvault: Enterprise-grade backup and recovery.
- AWS Backup: Cloud-native backup for Amazon services.
6. Best Practices for Backup and Recovery
- Test backups regularly to ensure recoverability.
- Encrypt sensitive backups for security.
- Automate backup schedules to avoid human error.
- Maintain a disaster recovery plan (DRP) and update it periodically.
7. Key Terminologies to Remember
- RPO (Recovery Point Objective): Maximum acceptable data loss (how often backups should occur).
- RTO (Recovery Time Objective): Time required to restore data after an incident.
- Snapshot: A point-in-time copy of data (quick but not a full backup).
8. Mnemonics for Quick Revision
- Backup Types: “Fully Different Increments”
- Full, Differential, Incremental.
- Recovery Sites: “Cold-Warm-Hot”
- Cold = Slow but cheap.
- Warm = Midway.
- Hot = Fast but costly.
- 3-2-1 Rule: “3 Copies, 2 Media, 1 Offsite”