High Availability & Disaster Recovery

Summary

High availability minimizes downtime through redundancy (multiple servers, multiple availability zones); disaster recovery is the plan for restoring service after a major failure — related but distinct concerns.

• 1Design a basic high-availability architecture with redundancy across at least 2 availability zones.
• 2Learn the difference between RTO (how fast you recover) and RPO (how much data you can afford to lose).
• 3Draft a simple disaster recovery plan for a hypothetical critical service.