Replication Failure Analyzer

Diagnose active replication failures by mapping symptoms to leader failover pitfalls, replication lag anomalies, or quorum edge cases — and produce a structured remediation plan. Use when: data just written disappears or shows stale on re-read (read-after-write violation); records appear and vanish on refresh (monotonic reads violation); causally related events appear in impossible order (consistent prefix reads violation); a failover produces duplicate primary keys, write rejections, or incorrect routing; two replica nodes are both accepting writes (split brain in replication topology — for split brain via distributed locking, use distributed-failure-analyzer); quorum reads return stale values despite w + r > n; or a sloppy quorum with incomplete hinted handoff is serving old data. Applies to PostgreSQL, MySQL (single-leader), Cassandra, Riak, Voldemort, DynamoDB (leaderless). Use replication-strategy-selector first if the topology has not yet been chosen. Produces: symptom → failure class → mechanism → mitigation report, leader failover checklist, replication lag anomaly guide, and quorum edge case catalog (six ways w + r > n still fails).

Install

Claude CodeClawhHubnpxCursorCodexGemini CLI

1. Add marketplace

› /plugin marketplace add bookforge-ai/bookforge-skills

2. Install plugin

› /plugin install designing-data-intensive-applications@bookforge-skills

3. Use the skill

› /replication-failure-analyzer

CC-BY-SA · Open sourceGitHub

Source Book

Designing Data-Intensive Applications

Martin Kleppmann

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