What's the difference between single-leader and multi-leader replication?
Single-leader replication routes all writes through one designated node, which then propagates changes to replicas — simple to reason about, since there's never a question of which write wins. Multi-leader replication allows writes to more than one node, useful for multi-region setups where each region wants local write latency, but it introduces the hard problem of resolving conflicting concurrent writes to the same data.
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Database Replication Explained: Single-Leader, Multi-Leader, and LeaderlessWhat replication lag actually breaks, and how single-leader, multi-leader, and leaderless models trade off consistency for availability.
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