The primary objective in a disaster recovery scenario is to restore service and functionality as quickly as possible to meet the organization's Recovery Time Objective (RTO). The RTO is the target time within which a business process must be restored after a disaster to avoid unacceptable consequences. Therefore, the most critical aspect to validate in a disaster recovery plan is the efficiency and speed of the backup restoration process itself. Testing this process provides a realistic measure of the actual downtime that will be incurred, allowing for optimization of procedures, scripts, and infrastructure to ensure the RTO can be met.

A. The total size of data backups is a factor in restoration time, but it is not the core process to assess; an efficient process can mitigate the impact of a large backup.

B. Compatibility is a prerequisite for a successful restore, not a measure of downtime. An incompatibility would cause the restore to fail, but the validation of speed assumes compatibility.

D. Physical distance is a strategic consideration for site resilience against regional events but does not directly influence the time it takes to execute the restoration command itself.

1. Official Vendor Documentation: Tableau Server Help

"Perform a Full Backup and Restore of Tableau Server." The documentation outlines the tsm maintenance restore command

which is the core of the recovery operation. The document states

"To validate your backup

you should perform a restore in a test environment." The purpose of such a validation is to ensure the process works and to time its execution

which directly relates to assessing its efficiency and speed.

Source: Tableau Server on Linux Help

Version 2023.3

"Perform a Full Backup and Restore of Tableau Server

" Section: "Restore from a backup."

2. University Courseware: In disaster recovery and business continuity planning

the Recovery Time Objective (RTO) is a foundational concept. Validating a DR plan involves testing to ensure the RTO can be achieved. This testing inherently focuses on the speed and efficiency of the recovery procedures.

Source: MIT Sloan School of Management

Course 15.575 (J)

"The Technology of Wargaming

" Lecture 10: Business Continuity. The lecture defines RTO as "The maximum tolerable length of time that a computer

system

network

or application can be down after a failure or disaster occurs." Assessing the restoration process (Answer C) is the direct method for validating the ability to meet this RTO.

3. Peer-Reviewed Academic Publication: Research on disaster recovery planning consistently identifies testing as a critical success factor. The goal of testing is to validate the plan's effectiveness

which includes the time required for recovery.

Source: Bajgoric

N. (2006). "Business continuity planning: a holistic approach." Information Management & Computer Security

14(5)

pp. 461-474. DOI: https://doi.org/10.1108/09685220610717757. The paper emphasizes that "BCP testing and exercising is the only way to find out if the developed plans are workable" (p. 469)

with workability being a function of both success and speed.