What Is a Consensus Quorum?
A consensus quorum is the majority of nodes whose agreement is required before a distributed cluster accepts a write or elects a leader. Requiring a majority ensures any two quorums overlap, so the system cannot commit conflicting decisions. If fewer than a quorum are reachable, the cluster stops accepting writes to preserve consistency.
Why it matters
Quorum is what lets a replicated store stay correct despite node failures and network partitions. Sizing clusters to an odd number keeps a clear majority available while tolerating failures.
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