Disaster recovery (DR)

Disaster recovery (DR) is the combination of plans, people, technology and procedures used to restore systems and data after a serious disruption. It should start from priority business processes, dependencies and approved RPO and RTO targets rather than from a replication product. Backup, high availability and DR are complementary: available data does not prove that identity, networks, applications and teams can operate. A plan should define who declares a disaster, communication, recovery order, acceptance criteria and return to normal service. Regular timed exercises should cover plausible failures and record results and exceptions. An untested document or a replica using the same administrative credentials can create confidence without recoverability. Evidence from restoration tests is more useful than a successful backup or replication status alone.