A disaster recovery plan is a documented process or set of procedures to recover and protect a business IT infrastructure in the event of a disaster. Having a disaster recovery plan is critical for any business that relies on IT systems and data to operate. There are four key components that make up a complete disaster recovery plan.
1. Business Impact Analysis
The business impact analysis (BIA) is one of the most important steps in developing a disaster recovery plan. The BIA determines and documents the potential impacts resulting from disruptions to business processes and IT systems in the event of a disaster. The BIA quantifies the business impact of system downtime and data loss in terms of financial losses and effects on business operations. This analysis allows an organization to identify and prioritize critical IT systems and components that require priority recovery time objectives (RTOs) and recovery point objectives (RPOs) to be determined for developing IT disaster recovery strategies.
The BIA involves identifying important business functions and processes, inventorying data and applications supporting those functions, and analyzing the consequences of various disaster scenarios to assess the potential impacts. This analysis helps to define IT systems and metrics needed for effective disaster recovery by determining:
- The maximum tolerable downtime for business-critical systems before unacceptable impacts occur.
- The minimum amount of data loss tolerable
- The financial impacts and risks associated with the disruption of operations
- Legal, regulatory, and contractual requirements for availability of systems and data.
The end result of the BIA is a list of prioritized systems, data, and metrics used to develop the disaster recovery strategy and detailed plans.
2. Disaster Recovery Strategies
The disaster recovery strategies provide methods and policies for restoring critical systems and data damaged or made unavailable by a disaster. The strategies are designed to meet the recovery objectives defined in the business impact analysis. Various disaster recovery strategies can be considered and implemented depending on the needs of the organization. Some common strategies include:
Backup and Restore
Regular backups of data, applications, and system configurations with offsite storage can enable restoration of critical systems and data. Backup schedules and retention policies must be defined to meet RTO/RPO requirements.
High Availability and Redundancy
Implementing high availability solutions and redundant infrastructure components can minimize downtime by eliminating single points of failure. This may involve failover clustering, redundant servers, storage replication, network redundancies, etc.
Multiple Processing Sites
Maintaining an alternate processing site or contracting disaster recovery services allows an organization to quickly restore operations if systems at the primary site are unavailable. Options include cold sites, hot sites, warm sites, mobile sites, and cloud-based services.
System Replacement
For less critical systems, an organization may decide that the most cost effective recovery method is to simply replace the components following a disaster event rather than investing in high availability solutions.
The strategies implemented will depend on the recovery time and data loss tolerances defined in the BIA. A combination of strategies may be required to fully mitigate all risks of downtime and data loss for essential systems.
3. Detailed Recovery Plans
Detailed, step-by-step recovery plans are essential for executing the strategies and processes needed to restore critical systems in the aftermath of a disaster. The plans should document the resources, procedures, and responsibilities required to facilitate recovery of each system. Considerations when developing recovery plans include:
- Documented recovery procedures for each system/component
- Order/sequence of recovery steps
- Recovery dependencies between systems and processes
- Personnel assignments for recovery tasks
- Contact information for recovery team and vendors
- Technology and resources required for recovery
- Recovery site details
- Verification testing steps
Recovery plans should cover processes for assessment, activation, notification, recovery implementation, and validation. The plans should enable recovery of the highest priority systems within the required RTO to minimize disruption to business operations.
Example Recovery Plan Outline
Here is an example basic outline of a recovery plan:
- Introductory Information
- Plan purpose and scope
- System/process overview
- Roles and responsibilities
- Assumptions
- Activation and Notification
- Damage assessment procedures
- Activation criteria/trigger
- Escalation procedures and contact information
- Recovery Procedures
- Prerequisites
- Detailed step-by-step procedures
- Personnel assignments
- Technology and resources required
- Validation and Testing
- Steps to verify successful recovery and functionality
- User acceptance testing
- Appendices
- Supporting information, configurations, contacts, forms, etc.
4. Testing and Exercises
Testing and exercises are critical for maintaining and validating the effectiveness of disaster recovery plans. Since actual disruptive events happen infrequently, testing provides a way to verify that the recovery procedures are accurate and complete. Testing identifies any gaps or issues in the plans before a real crisis occurs. Some important aspects of disaster recovery testing include:
- Develop a testing schedule – Establish a regular cadence for conducting tests such as quarterly, semi-annually, or annually. The frequency should be based on the criticality of the systems and recovery time objectives.
- Test a wide range of scenarios – Perform tests that simulate different types of disasters and recovery scenarios to ensure robustness.
- Test technical components and procedures – Verify that backups are valid, systems failover/transfer work, recovery steps are accurate and complete.
- Test user procedures – Validate that users understand recovery processes and can execute their roles.
- Test third-party dependencies – Confirm vendors and suppliers are ready to deliver on their responsibilities for supporting recovery.
- Alternate recovery sites/facilities – Conduct tests to ensure alternate processing sites, equipment, and data meet requirements.
- Document and assess – Document test results thoroughly including problems encountered, steps performed, and duration. Identify actions for improving plans.
Common types of disaster recovery testing exercises include:
Tabletop Exercises
Tabletop exercises simulate an emergency situation in an informal discussion setting. Participants talk through recovery procedures and scenarios without any technical recovery actions being performed. This tests the overall understanding of roles, processes, and dependencies in the plan.
Walkthrough Tests
A walkthrough test executes the disaster recovery procedures in a non-technical run-through. The purpose is to validate technical steps, timing, and personnel assignments.
Simulation Tests
Simulation testing isolates and tests specific components and capabilities without disrupting the entire live system. For example, this may involve restoring backups to an alternate facility to verify recoverability.
Parallel Testing
Parallel testing activates the disaster recovery capabilities in an isolated environment while normal business operations continue. This comprehensive test assesses the overall recovery process with minimal disruption.
Cutover Testing
A cutover test transitions business operations from the primary system to the recovered alternate environment to verify functionality. The most disruptive test, this validates recovery capabilities under production conditions.
A robust disaster recovery testing program provides ongoing assurance and improvement of an organization’s ability to recover from disruptions. Testing should be recurring to account for changes in technology, business processes, personnel, and recovery strategies over time.