DisasterRecovery

Disaster recovery refers to the processes, policies, and procedures put in place to restore information technology (IT) systems and data after a disruptive incident. It is a subset of business continuity planning and focuses on restoring critical IT infrastructure, applications, and data to support essential operations with minimal downtime.

Disaster recovery objectives are commonly expressed as recovery time objective (RTO) and recovery point objective (RPO). RTO defines the maximum acceptable downtime for a service, while RPO indicates the age of data that must be recovered. Plans are tailored to the criticality of systems, regulatory requirements, and budget.

Key components include a data backup strategy, data replication, failover mechanisms, and alternative processing sites. Plans describe roles, communication channels, escalation procedures, and decision authorities. DR options range from on-site backups to cloud-based solutions, including hot sites (ready to operate), warm sites (partially equipped), and cold sites (basic infrastructure).

Disaster recovery follows a lifecycle: risk assessment and business impact analysis, strategy selection (sourcing, rearchitecting, or outsourcing), plan development, implementation, training, testing, and maintenance. Regular tests such as table-top exercises and failover tests verify readiness and reveal gaps.

Governance and standards provide guidance. Examples include ISO 22301 for business continuity management, ISO 27031 for information and communication technology readiness and support, and NIST guidelines for contingency planning. Compliance requires documentation, evidence of testing, and ongoing improvements.

DR readiness is increasingly supported by cloud services, immutable backups, and automation to reduce recovery times and errors. Organizations aim to balance resilience with cost, regulatory obligations, and user expectations.