Consensus & Coordination Control Plane

Overview

Build a leader/follower coordination flow with explicit quorum registry and election control.

Consensus is about who is allowed to decide.

You will build 6 architecture steps that model production dependencies.

You will run 1 failure experiment to observe bottlenecks and recovery behavior.

Success target: Leader failover occurs within target window while preserving ordered replication semantics.

Learning Objectives

• Can explain practical consensus control-plane components
• Can defend quorum/election tradeoffs under failures
• Can discuss leader failover timing in interviews

Prerequisites

• Topic Hub: leader election
• Chapter 25: Consensus
• Prior Lab: Database Replication & Read Scaling

Experiments

1. Increase failover time to simulate prolonged unavailability after leader failure