nexus/Archived/Work/SG Yearly DR Execution Plan (EFS Replication Only).md

title, source, author, published, created, description, tags

title	source	author	published	created	description	tags
		shenwei

1. Objective

Ensure business continuity and data protection by implementing an effective DR strategy for the customer, leveraging EFS replication, RDS PITR, and different failover methods.

2. DR Scenarios & Recovery Options

	Method	RDS Recovery	EFS Recovery	Failover Steps	Estimated Downtime (RTO)	RPO	Cost Impact
DR Basic Service	Cold Backup-Restore	Snapshot (6h)	Backup Restore (6h)	1. Restore RDS from snapshot (6h) 2. Restore EFS from snapshot (6h) 3. Recover EKS (4h)	24 hours	4 hours	Base Cost
DR Premium Service	EFS Replica Only (RDS PITR)	PITR (6h)	EFS Replica + Restore (0.2h)	1. RDS recovery from PITR (6h) 2. Stop EFS sync (0.2h) 3. Full EKS recovery	6 hours	15 min	+30% Cost

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3. Downtime Estimation & RTO Considerations

• EFS Replica Only (RDS PITR)
  • 6-hour RTO, significantly reducing downtime compared to cold restore.
  • 15-minute RPO ensures minimal data loss.

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4. DR Execution Plan

4.1 Pre-DR Readiness Checks

• Ensure EFS replication is active and functioning correctly.
• Verify RDS PITR backups and retention policies.
• Pre-configure EKS deployment templates(Velero) for rapid recovery.

4.2 Disaster Recovery Trigger

• DR activation is initiated upon a major failure event in the primary environment.
• Decision criteria include regional failure, prolonged service outage, or severe data corruption.

4.3 Execution Steps

EFS Replica Only (RDS PITR)

1. Recover RDS from PITR (6 hours).
2. Stop EFS replication sync (0.2 hours).
3. Recover EKS cluster and validate application (immediate).

4.4 Post-Failover Validation

• Confirm data consistency between DR and primary environments.
• Validate application services and connectivity.
• Communicate DR activation and service restoration to stakeholders.

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5. DR Testing & Cost Estimation

• Annual DR validation test is required, adding an estimated 2 months of AWS costs.
  • EFS Replica Only (RDS PITR):
    • $20.8K/month