Microsoft Certified: DevOps Engineer ExpertImplement a Site Reliability Engineering (SRE) strategyMedium
A global e-commerce company uses Azure Front Door to route traffic to its multi-region application. The SRE team wants to ensure that if one Azure region experiences a major outage, user traffic is automatically and seamlessly redirected to a healthy region with minimal disruption. They also aim for near-zero RTO and RPO. Which disaster recovery strategy should they employ?
- ABackup and Restore with Geo-redundant Storage
- BPilot Light with Azure Site Recovery
- CActive-Active with Azure Front Door
- DWarm Standby with Azure Traffic Manager
Show answer & explanationAnswer & explanation
Correct answer: C. Active-Active with Azure Front Door
An Active-Active (Hot Standby) strategy with Azure Front Door is ideal for near-zero RTO and RPO. Azure Front Door inherently provides global load balancing and health probes, automatically routing traffic to the healthiest backend in multiple active regions, ensuring seamless failover and high availability.
Why the other options are wrong
- A. Backup and Restore has high RTO/RPO and is unsuitable for 'near-zero' requirements.
- B. Pilot Light requires manual or automated spin-up of compute, leading to a non-zero RTO, and Azure Site Recovery is typically for IaaS VMs, not a pure PaaS solution with Front Door.
- D. Warm Standby still involves scaling up resources, resulting in a non-zero RTO, and while Traffic Manager provides DNS-level routing, Front Door offers more advanced application-level routing and caching for global applications.
Active-Active DR (Hot Standby)
A disaster recovery strategy where full, identical application environments run simultaneously in multiple regions, distributing live traffic and providing immediate failover capabilities.
- Achieves near-zero RTO and RPO.
- Highest cost due to duplicate active infrastructure.
- Requires global load balancing (e.g., Azure Front Door, Traffic Manager).
Memory trick: Active-Active regions keep traffic flowing without a single hiccup.