According to the CISSP All-in-One Exam Guide1, the most important consideration when developing a Disaster Recovery Plan (DRP) is to have a recovery strategy for all business processes. A DRP is a document that defines the procedures and actions to be taken in the event of a disaster that disrupts the normal operations of an organization. A recovery strategy is a plan that specifies how the organization will restore the critical business processes and functions, as well as the supporting resources, such as data, systems, personnel, and facilities, within the predefined recovery objectives and time frames. A recovery strategy should cover all business processes, not just the IT-related ones, as they may have interdependencies and impacts on each other. A recovery strategy should also be aligned with the business continuity plan (BCP), which is a document that defines the procedures and actions to be taken to ensure the continuity of the essential business operations during and after a disaster. The dynamic reconfiguration of systems is not the most important consideration when developing a DRP, although it may be a useful technique to enhance the resilience and availability of the systems. The dynamic reconfiguration of systems is the ability to change the configuration and functionality of the systems without interrupting their operations, such as adding, removing, or replacing components, modules, or services. The dynamic reconfiguration of systems may help to reduce the downtime and recovery time of the systems, but it does not address the recovery of the business processes and functions. The cost of downtime is not the most important consideration when developing a DRP, although it may be a factor that influences the recovery objectives and priorities. The cost of downtime is the amount of money that the organization loses or spends due to the disruption of its normal operations, such as loss of revenue, productivity, reputation, or customers, as well as the expenses for recovery, restoration, or compensation. The cost of downtime may help to justify the investment and budget for the DRP, but it does not address the recovery of the business processes and functions. A containment strategy is not the most important consideration when developing a DRP, although it may be a part of the incident response plan (IRP), which is a document that defines the procedures and actions to be taken to detect, analyze, contain, eradicate, and recover from a security incident. A containment strategy is a plan that specifies how the organization will isolate and control the incident, such as disconnecting the affected systems, blocking the malicious traffic, or changing the passwords. A containment strategy may help to prevent or limit the damage and spread of the incident, but it does not address the recovery of the business processes and functions. References: 1
