advancedHigh Availability: Multi-Node Control Plane & Leader Election
Why are etcd clusters deployed with an odd number of nodes instead of an even number?
etcd requires a majority (quorum) of nodes to agree before a write is committed — an odd count (3 or 5) guarantees a network partition always leaves at most one side with a clear majority, while an even count (like 4) can split evenly with neither side able to reach quorum at all.
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