Uplicesheni inaendelea kwa kumiliki nakala za data katika seva nyingi — kwa kufikiwa (kubaki hai baada ya kushindwa), kubadilisha kwa kusoma (kutumia kusoma kutoka kwa nakala), na kusambaza kwa kijiografia. Mkakati tofauti (mkuu-nakala, wengi-mkuu, sawa na isiyo sawa) inahusisha mapendo.
Kwa nini kuplicesheni
✓ AVAILABILITY/redundancy → if one copy fails, others have the data (no data loss, failover)
✓ READ SCALING → serve reads from replicas (offload the primary) → handle more reads
✓ GEO-DISTRIBUTION → copies near users (lower latency); disaster recovery
→ replication is fundamental to reliable, scalable data systems.
