Database Replication Topologies Visualized: Leader, Multi-Leader, and Quorum
An animated trace of the five replication topologies — single leader, multi leader, leaderless, quorum, and chain — with a live node failure injected into each one. We watch where the write goes, which nodes acknowledge it, and what the reader sees one millisecond later. Replication looks like a copying problem until a node dies; then it becomes a question of who decides what the truth is. We show the same failure in each topology so the trade-off between write availability and read consistency is visible side by side.
Topics covered:
- Single leader: the replica lag read
- Multi leader: conflict resolution when two writes win
- Leaderless and quorum: the read repair gap
- Split brain and why fencing matters
- Picking a topology from your consistency budget
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