The original title is: "Day 77 of #100DaysOfClickHouse: Resolving Replication Conflicts in ClickHouse®"

Short summary

A technical guide to identifying, troubleshooting, and resolving replication conflicts in ClickHouse clusters using ReplicatedMergeTree. Covers the replication workflow through ClickHouse Keeper, common problems like read-only replicas and growing replication queues, and provides SQL queries against system tables to diagnose each issue. Aimed at operators running ClickHouse in production.

• •ClickHouse replicates immutable data parts via ClickHouse Keeper, not row-level changes
• •System tables like system.replicas and system.replication_queue expose replica health and queue status
• •Common issues include read-only mode, growing queues, missing parts, and Keeper connection failures

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