Redis yana ba da high availability ta hanyar replication (kwafin kwafin bayanan), Redis Sentinel (automated failover monitoring), da Redis Cluster (sharding + replication). Fahimtar wannan abu yana da muhimmanci don aiki da Redis cikin ƙarfi a production.
Replication — primary da replicas
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
