A system needs RTO/RPO measured in minutes — much cheaper than active-active but able to serve traffic after scaling up. Which DR pattern fits?
A.Backup and restore
Hours of RTO — doesn't meet minutes.
B.Pilot light
Pilot light has nothing running to serve traffic — only essentials replicated.
C.Warm standby — a scaled-down but functional copy running in the DR region
Correct. Live at low capacity, scales on failover.
D.Multi-site active-active
Meets the RTO but at full duplicate cost — not the 'cheaper' answer.
Why this answer
Warm standby runs a minimum-capacity but WORKING environment in the DR region — failover = scale up + route traffic. Pilot light keeps only data + minimal core components (nothing serving); backup/restore is hours-scale. The exam loves the four-tier DR ladder: backup → pilot light → warm standby → active-active.
Correct answer: C · Last reviewed 2026-11-03
Official AWS references
Practice this interactively
Answer without seeing the solution first in the Complex Solution Design practice session.
Practice Complex Solution Design