How does active-passive failover fail?
Active-passive requires human administrators to detect failure, then manually promote a standby node to primary. This manual step is slow, error-prone, and leaves the cluster unavailable during the detection window, especially when the partition heals and creates ambiguity about which node is truly primary.
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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