A company has critical business data on on-premises servers and uses AWS for disaster recovery. When the on-premises site fails, the AWS environment must immediately serve production traffic — even at reduced capacity — with no time spent first starting servers, and without paying for a full-scale second production environment. Which DR strategy fits best?
Show answer and explanation
Answer: C
Warm standby keeps a scaled-down but genuinely running copy of the workload in AWS at all times, so the moment the on-premises site fails, the AWS side can accept production traffic immediately and then scale out to full capacity. It avoids the startup-and-scale delay of lighter strategies without doubling the footprint the way active/active does.
This is the standard match for an immediate-service requirement at a non-double cost.
Why the other options are wrong
- A. Rebuilding from cold-storage snapshots means restoring infrastructure and data before serving any request, which is the slowest recovery and cannot meet an immediate-service requirement.
- B. Pilot light leaves the application servers powered off, so after failover there is an unavoidable launch-and-scale interval before traffic can be served.
- D. Running full production in both sites serves traffic instantly but at double the infrastructure cost, which the company explicitly does not want to pay.