Recovery Time Objective (RTO) is the duration of time within which a business process must be restored after a disaster to avoid unacceptable consequences. In this scenario, the system went down at 16:00 and resumed operation at 23:00. The total downtime, or actual recovery time, is 7 hours (23:00 - 16:00).

Recovery Point Objective (RPO) is the maximum tolerable period of data loss. It measures the time from the last recoverable data point to the point of failure. Here, the failure occurred at 16:00, and the data was restored to its state at 12:00. Therefore, the amount of data lost corresponds to a 4-hour period (16:00 - 12:00).

A. This option incorrectly swaps the calculated values for RTO and RPO. RTO measures time to recover, while RPO measures the period of data loss.

C. This option incorrectly calculates the RTO. The downtime was 7 hours, not 2 hours.

D. This option incorrectly calculates the RPO. The data loss period was 4 hours, not 3 hours.

1. Huawei HCIA-Storage V5.0 Training Material. In the "Backup and Disaster Recovery Technologies" chapter

RTO is defined as the maximum tolerable service interruption time

and RPO is defined as the maximum tolerable data loss. The calculations in this question directly apply these official definitions. (Reference: Huawei Certified ICT Associate - Storage V5.0

Training Material

Chapter 7: Backup and Disaster Recovery Technologies

Section 7.1.2: Basic Concepts of Disaster Recovery).

2. Huawei Cloud Disaster Recovery Solution White Paper. This document defines key disaster recovery (DR) indicators. It specifies RTO as the target time for restoring a service after a disaster and RPO as the target time point to which data needs to be restored

representing the amount of data that can be lost. (Reference: Huawei Cloud Disaster Recovery Solution White Paper

Section 2.1: Key DR Indicators).

3. Academic Publication. In academic literature on business continuity

RTO is consistently defined as the time it takes to recover from a disaster

while RPO is the acceptable data loss measured in time before the disaster. (Reference: Wibowo

W. T.

et al. "A survey on disaster recovery for cloud data centers." International Journal of Communication Systems

vol. 31

no. 17

2018

e3808. Section 2: Background and Related Works. DOI: https://doi.org/10.1002/dac.3808).