What is disaster recovery (DR)?

Disaster recovery (DR) refers to the strategies and processes an organization uses to restore critical systems, applications, and data after an unexpected event disrupts normal operations. These events could include hardware failures, cyberattacks, natural disasters, or human errors. The primary goal of DR is to minimize downtime and data loss, ensuring business continuity. For developers, this often involves designing systems with redundancy, backups, and failover mechanisms. Unlike simple backups—which focus on data preservation—DR encompasses a broader plan for recovering entire workflows, services, and infrastructure in a structured way.

A common example of DR is maintaining off-site backups of databases and application code. For instance, a company might use cloud storage to replicate data across geographically separate regions. If a server farm goes offline due to a power outage, traffic can be redirected to a secondary site. Developers might implement automated scripts to spin up replacement servers or restore databases from snapshots. Another example is defining recovery time objectives (RTOs) and recovery point objectives (RPOs). An RTO of two hours means systems must be restored within that window, while an RPO of 15 minutes limits data loss to the last 15 minutes before the outage. These metrics guide technical decisions, like how frequently backups are taken or how quickly failover systems must activate.

Effective DR requires regular testing and updates. Developers might simulate disasters—like shutting down a data center—to validate recovery steps. Tools such as infrastructure-as-code (IaC) templates or container orchestration platforms (e.g., Kubernetes) help rebuild environments quickly. Monitoring and alerting systems also play a role by detecting issues early, potentially avoiding full-blown disasters. For example, automated alerts for disk space shortages or unusual network traffic patterns can trigger preemptive fixes. While DR planning adds complexity, it’s a necessary investment to ensure systems remain resilient and users experience minimal disruption during crises.