consensus

Definition

The problem of getting a set of machines to agree on a single value or a single ordering despite crashes, message loss, and delay. It underpins replicated databases, distributed locks, and leader election, with Paxos and Raft as the canonical solutions. The crucial part is safety: once a value is decided, no correct node may ever decide differently — agreement here is irrevocable, not just a majority vote.

Explainers using this term

• Distributed Databases — CAP, Replication and ConsensusIn Search of an Understandable Consensus Algorithm (Raft) — Diego Ongaro