For a new three-tier application, the design team has implemented Pilot Light DR (Disaster Recovery) strategy between production servers deployed at AWS us-east-1 region & backup servers deployed at on-premises data centers. Management needs to understand the impact of implementing Pilot Light DR strategy in a network in terms of RTO / RPO.
Which is the correct statement to justify this?

Answer options:

A.RPO will be in hours, while RTO will be less than 24 hours.
B.RPO will be zero while RTO will be potentially zero.
C.RPO will be in seconds, while RTO will be in minutes.
D.RPO will be in minutes while RTO will be in hours.

Correct Answer: D
RTO is the maximum acceptable delay between the interruption once disaster strikes and restoration of service. RPO is the maximum acceptable amount of time since the last data recovery point at which all data is replicated to the DR location.
With Pilot Light DR Strategy, data replication between production & backup databases is always active. Application servers in the DR location are configured but are in shut mode. With this strategy, when there is a disaster, loss in data will be in minutes while it will take hours to initiate application servers in the DR location.
Options A, B & C are incorrect as with Pilot Light DR strategy, RPO will be in minutes & RTO will be in hours. Following will be RTO/RPO values for each DR strategy,
Backup and restore: RPO will be in hours, while RTO will be less than 24 hours.
Pilot light: RPO will be in minutes while RTO will be in hours.
Warm standby: RPO will be in seconds, while RTO will be in minutes.
Multi-region (multi-site) active-active: RPO will be zero while RTO will be potentially zero.
For more information on RTO/RPO with different DR strategies, refer to the following URL,
https://docs.aws.amazon.com/wellarchitected/latest/reliability-pillar/plan-for-disaster-recovery-dr.html