[Redis] Redis Cluster vs Redis Sentinel

1) In-Depth Guides to Redis Cluster and Sentinel

For more in-depth explanation for Redis Cluster or Redis Sentinel, please read my other posts:

2) Deciding between Redis Sentinel and Redis Cluster

Similarities: Both solutions provide high availability for your system.

2.1) Redis Cluster

2.1.1) Pros

  • Shards data across multiple nodes
  • Has replication support
  • Has built-in failover of master

2.1.2) Cons

  • Not every library supports it
  • May not be as robust (yet) as Standalone Redis or Sentinel
  • Setup and maintenance is more complicated

2.2) Redis Sentinel

2.2.1) Pros

  • Automatically selects new master in case of failure
  • Easy to setup, (seems) easy to maintain

2.2.2) Cons

  • No data sharding; master might be overutilized.
  • Another distributed system to maintain.

3) So how do I decide?

In short, if you need high availability without full cluster (data sharding), use Sentinel! It is easier to setup and maintain. If you need data sharding between multiple nodes, then use clustering.

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