Redis Cluster for Sharding

So far, we've learned about Redis replication and Sentinel for high availability. These are great for redundancy and read scaling, but what about write scaling or handling datasets larger than a single server's memory?

This is where Redis Cluster comes in. It's designed to provide horizontal scaling and fault tolerance by distributing your data across multiple Redis instances.

At its core, Redis Cluster uses sharding (also known as data partitioning). Imagine you have a massive library of books.

• Instead of one giant shelf, you split the books across many smaller shelves.
• Each shelf holds a portion of the books, and a librarian manages that shelf.

In Redis Cluster, each Redis instance (or node) acts like a 'librarian' managing a 'shelf' of your data. This allows you to scale both memory and CPU.