You are a site reliable engineer in a company. Your company has a new application deployed in AWS that has three tiers including frontend, backend and database. Various AWS services are being used such as EC2, ELB, Auto Scaling, Route53, RDS, etc. For the whole application, the RTO (recovery time objective) is set to 1 hour. Which approach can help you the most to achieve this target?

Answer options:

A.In RDS, configure each database to create regular automated snapshots every hour. Copy the snapshots to another region.
B.Create a warm standby in another region. Use Route53 failover routing policy to route to the standby if the active application has an outage.
C.Create regular EBS snapshots every hour using EBS lifecycle manager.
D.Create a Jenkins pipeline to automatically create AMIs for EC2 instances. Execute the pipeline every hour.

Correct Answer – B
The question asks for the approach that can help the most to achieve the target. The application contains several components and all of them should be considered.
The RTO (recovery time objective) is set as 1 hour, which means the application should recover within 1 hour after the outage. The question does not mention the RPO (Recovery Point Objective).
Option A is incorrect: It only helps on RDS and it does not mention how to deal with other components. Besides, the automatic snapshots mainly help on RPO since the data is backed up frequently.
Option B is CORRECT: This is a standard approach to help achieve a short RTO. It can reduce the recovery time because most of the service is always running in warm standby.
Option C is incorrect: Because it is only related to EBS and mainly helps on achieving RPO instead of RTO.
Option D is incorrect: Similar with Option
C. This option can be regarded as an option to help meet the RPO target.