Redis zagotavlja visoko razpoložljivost prek replikacije (kopije podatkov na replikah), Redis Sentinela (avtomatsko spremljanje failoverjenja) in Redis Clustra (sharding + replikacija). Razumevanje teh konceptov je pomembno za zanesljivo obratovanje Redis-a v produkciji.
Replikacija — primarni in replike
PRIMARY (master) → handles writes; asynchronously replicates data to replicas
REPLICAS (slaves) → copies of the primary's data; can serve READS (read scaling)
Write → Primary → async replication → Replicas (eventually consistent)
✓ Redundancy (replicas have copies) + read scaling (reads offloaded to replicas)
✗ Replication is ASYNC → a small lag; a failover could lose very recent writes
