Clustering & HA

This module explores the core principles of Redis Clustering and High Availability, focusing on first principles and distributed system constraints. You will learn how Redis scales horizontally while maintaining high availability.

Module Contents

1. Sharding & Hash Slots

Learn why Redis Cluster uses 16,384 hash slots and how keys are distributed using CRC16.

2. Topology & Gossip

Understand the P2P mesh architecture, the Cluster Bus, and how nodes gossip to detect failures.

3. Smart Clients & Redirection

Discover how clients find the right node using MOVED and ASK redirection errors.

4. Resharding & Scaling

A deep dive into online scaling, moving slots between nodes, and the MIGRATE command.

5. High Availability & Failover

How Redis Cluster automatically recovers from node failures using Replica Election and Raft-like consensus.

Review & Cheat Sheet

Test your knowledge with flashcards and a quick reference guide.

Module Chapters