Backup and recovery in disaster recovery (DR) are processes designed to protect data and restore systems after a disruption. Backup involves creating copies of data, configurations, and applications, stored in a separate location from the primary systems. Recovery is the process of restoring these backups to resume operations. In DR, the goal is to minimize downtime and data loss during events like hardware failures, cyberattacks, or natural disasters. For example, a company might use nightly backups of databases and virtual machine snapshots to ensure they can rebuild systems quickly if a server farm goes offline.
Effective backup strategies in DR focus on frequency, retention, and storage location. A common approach is the 3-2-1 rule: keep three copies of data, on two different media types, with one offsite. For instance, a developer might configure daily incremental backups to a local network-attached storage (NAS) device and weekly full backups to a cloud provider like AWS S3. Recovery strategies define objectives such as Recovery Time Objective (RTO), which specifies how quickly systems must be restored (e.g., 4 hours), and Recovery Point Objective (RPO), which determines the maximum acceptable data loss (e.g., 1 hour of transactions). Automated tools like Veeam or Azure Backup simplify scheduling and verifying backups, while scripts can test recovery workflows.
Challenges in backup and recovery include balancing cost, complexity, and reliability. Large datasets may require tiered storage or deduplication to manage costs. For example, a video streaming service might prioritize backing up metadata daily but archive raw video files less frequently. Recovery can fail if backups are corrupted, so checksums or integrity tests are critical. Developers must also plan for scenarios like ransomware encrypting both primary and backup systems—a risk mitigated by air-gapped backups or immutable cloud storage. Regular drills, such as simulating a database restore from backups, help teams identify gaps in their DR plans before real disasters occur.