What is split-brain and why is it dangerous?
Split-brain occurs when a network partition causes two parts of a cluster to operate independently, each believing it is the primary. Both partition leaders accept writes, diverging data and corrupting consistency. On network healing, the diverged states cannot merge automatically.
Answered in
Why Raft Consensus Prevents Split-BrainRaft ensures only one partition can reach quorum, making split-brain impossible. Writes commit to majorities. Powers etcd and CockroachDB.
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