💾 Data Backup Strategy

1. Backup Types

• Full Backup: Captures all data; longest to complete and store.
• Incremental Backup: Saves changes since the last backup; fastest and most space-efficient.
• Differential Backup: Saves changes since the last full backup; balance between time and space.

2. Local vs Cloud Backups

• Local: On-premise storage like NAS, tapes, or external drives. Fast access but vulnerable to physical disasters.
• Cloud: Remote storage via AWS S3, Google Cloud Storage, or Azure Blob. Redundant, scalable, and secure.
• Best practice: follow the 3-2-1 rule (3 copies, 2 mediums, 1 offsite).

3. Retention Policies

• Define how long different types of data are retained.
• Use tiered storage to move old data to cheaper, slower storage (e.g., Glacier, Coldline).
• Ensure compliance with regulations like GDPR, HIPAA.
• Automate purging of expired backups.

4. Encryption & Storage Security

• Encrypt data at rest and in transit using AES-256 or TLS 1.2+.
• Use secure key management systems like AWS KMS or HashiCorp Vault.
• Enable MFA and RBAC for accessing backup infrastructure.
• Log and monitor access to backup systems.

5. Restore & Testing

• Periodically test restore processes to ensure integrity and speed.
• Document step-by-step recovery procedures.
• Automate restore drills for mission-critical systems.
• Include RTO (Recovery Time Objective) and RPO (Recovery Point Objective) in planning.