Fundamentals of Data Replication, Backup, and Disaster Recovery

Data replication software is traditionally used for disaster recovery scenarios such as backup, business continuity, and disaster drills, ensuring data safety and uninterrupted services.

The two key metrics for evaluating a disaster‑recovery system are Recovery Time Objective (RTO), the maximum tolerable downtime, and Recovery Point Objective (RPO), the maximum tolerable data loss.

Based on recovery goals and cost, disaster‑recovery levels are classified as data‑level, application‑level, and business‑level, with higher levels requiring greater investment.

Cloud disaster recovery (DRaaS) treats disaster recovery as a service; tenants configure backup rules on a management platform, facing challenges such as limited bandwidth and the need for robust compression and resumable transfer capabilities.

Backup fundamentals include scheduled (timed) backup and real‑time backup; continuous data protection (CDP) provides near‑real‑time backup, overcoming traditional periodic backup limitations.

Backup methods are also categorized by data volume: full backup (entire dataset), incremental backup (only changes since the last backup), and differential backup (changes since the last full backup), each with distinct storage and time trade‑offs.

Copy Data Management (CDM) reduces storage consumption by eliminating redundant copies across applications, often using a “full‑once plus permanent incremental” approach for rapid data capture and restoration.

Deduplication removes duplicate data blocks, while compression reduces data size without loss, both improving storage efficiency and transmission speed.

Backup can target different objects: block‑level backup (disk sectors), file‑level backup (files via filesystem interfaces), and database backup (tables, logs, etc.), with block‑level generally offering higher efficiency.

Disaster recovery also involves concepts such as two‑site three‑center architectures, high availability (HA), active‑standby and active‑active configurations, and distinguishes HA from full disaster recovery solutions.

The article concludes with references to the original Chinese Data Replication Industry White Paper (2022) and includes promotional material for purchasing comprehensive technical document packages.