ElastiCache Redis Cluster Modes¶

ElastiCache Replication: Cluster Mode Disabled¶

• One primary node, up to 5 replicas
• Asynchronous replication
• The primary node is used for read/write
• The other nodes are read-only
• One shard, all nodes have all the data
• Guard against data loss if node failure
• Multi-AZ enabled by default for failover
• Helpful to scale read performance

ElastiCache Replication: Cluster Mode Enabled¶

• Data is partitioned across shards (helpful to scale writes)
• Each shard has a primary and up to 5 replica nodes (same concept as before)
• Multi AZ capability
• Up to 500 nodes per cluster
  • 500 shards with a single master
  • 250 shards with 1 master and 1 replica ...
  • 83 shards with one master and 5 replicas